People respond to incentives—people make decisions by comparing the costs and benefits of a particular action. When either the costs or benefits change, behavior also changes. My dissertation focuses on estimating the impact of two different behaviour-altering taxes on household consumption. In the first section, I conduct an empirical examination of a hypothetical "fat tax" on household food consumption in Canada. The simulation results suggest that when fat tax revenues are recycled as lump-sum transfers to households, this policy would be the most efficient and progressive scenario from both economic and health perspectives. In the second section, I examine the impact of British Columbia's (BC) recently implemented carbon tax on household energy use from an aggregate perspective. I find no significant impact of the BC carbon tax on residential natural gas consumption. The third section is a further investigation of the BC carbon tax on household natural gas consumption varied by their environmental ideology. The results suggest that the impact of the carbon tax is more effective for non-environmentally conscious households than for other households.

遺產及贈與稅的課徵具有實現社會公平的正面意義，但開徵至今，不僅稅收不豐，更因租稅規避行為普遍而失去效率，我國遂於2009年針對遺產及贈與稅制進行大幅改革。 　　本研究以美國、香港及新加坡的稅制實施與改革經驗為借鏡，輔以財政部國稅局的實際課徵數據，探討此次遺贈稅制改革的內容與影響。研究發現，此次遺贈稅改的影響，於短期會造成遺贈稅的稅收損失，但就長期而言，因稽徵效率提升及降低民眾跨期與跨區配置資源的條件限制，可增進整體社會資源的配置效率。此外，調降後的遺贈稅稅率約與租稅規劃成本相當，可望減緩我國資金外流的情形；惟仍須配合國內政治、經濟及社會環境之發展，方有足夠誘因吸引資金回流。 　　是故，本研究建議政府機關應有明確之政策發展方向，如欲以租稅政策促進經濟發展，應先正視我國目前面臨的競爭環境及資金流向問題，塑造優良投資環境，方能吸引資金回流，活絡我國經濟並培養適當稅源。再者，亦應確立遺贈稅制之定位，於未來改革方向，不論再降稅或廢除，均應規劃妥善之配套措施，使我國整體賦稅制度更臻完善。 / The estate and gift taxes are most often justified by the need to ensure a particular sense of fairness in the overall tax system. However, the two contribute to a rather insignificant share to total tax collection, and also encourage widespread tax avoidance. Thus, many economists argue that the estate and gift taxes are hard to justify on either efficiency or equity grounds. For these reasons, the Estate and Gift Tax Act in Taiwan was substantially revised in January, 2009. The main purpose of this study is to explore the major revisions and the impact of the tax reform, supported by the financial statistics offered by the Ministry of Finance, R.O.C. The results of this study indicate that the significant revision will lead to a reduction in tax revenue in the short term. Neverthetheless, it will make the allocation of resources in the economy more efficient in the long term, since the collection efficiency of the two taxes improves and the restriction on allocation of resources for the public is reduced. Besides, the new tax rate is nearly equal to the cost of tax planning, so the capital outflow may be eased off. If the government and regulatory bodies also improve the investment environment, it will attract more foreign capital back to Taiwan. Based on the above, this study provides some suggestions for the tax administration. First, it is necessary to set a clear policy direction. If policy makers intend to use tax policies as a tool for promoting economic development, it is important to address the issues which our country currently encounters with, including the competitive economic environment and where the capital flows to. Only with the better investment environment, can our country attract more international capital to invest in. Second, tax administration must establish the role played by estate and gift taxation in our tax system. Any reforms of the estate and gift taxes must entail a set of complementary measures, so that our tax system could be fairer and more efficient.

We use survey findings to analyse the effects of the Austrian income tax reform 2015/2016 on private consumption differentiated by income classes. Using survey data, we also estimate the corresponding average marginal propensities to consume and compare them to applied average marginal propensities to consume in economic models used to analyse the previous two income tax reforms in Austria. The estimated average marginal propensity to consume amounts to approximately 0.46, whereby in tendency increasing from the lowest income class (0.42-0.43) to the highest income class (0.48-0.50). Our estimated average marginal propensity to consume across all income classes basically corresponds to those used in economic models to evaluate the income tax reform 2015/2016. However, our estimated marginal propensities to consume by income classes fundamentally differ from those used in the economic models. / Series: Department of Economics Working Paper Series

Alterações na legislação tributária sempre motivaram profundas discussões políticas e acadêmicas. Isso ocorre pois mudanças dessa natureza promovem a realocação dos fatores de produção, alterando a produção de setores e regiões, e, consequentemente, da receita arrecadada pelos governos. Essa última, por sua vez, é alterada por duas motivações: as variações das alíquotas e as da própria base tributária. O sistema tributário brasileiro, ao longo do tempo, passou por constantes reformulações buscando torná-lo mais moderno e adequado às condições econômicas e políticas vigentes. Entretanto, atualmente, diferentemente do que ocorreu no passado, não é mais possível prover reformas tributárias lastreadas no aumento da carga, uma vez que essa já assume patamares incompatíveis com o grau de desenvolvimento do País. Nesse cenário, apresenta-se a PEC nº 233/08, a mais recente proposta de reforma tributária que, buscando manter inalterada a carga tributária no patamar atual, propõe, entre outras mudanças, modificações relevantes na legislação do ICMS. Esse projeto de emenda constitucional propõe a harmonização da legislação do ICMS e a preservação do sistema misto de apropriação do imposto entre origem e destino, aumentando significativamente, porém, a apropriação pelo destino. Dada a necessidade de uma abordagem empírica para as discussões, essa tese, com o objetivo de estimar os impactos decorrentes dessa proposta de reforma, utilizou um modelo de equilíbrio geral computável inter-regional denominado BMARIA- RS-TAX (ano-base 2004), que investigou as relações econômicas entre o Rio Grande do Sul e o Restante do Brasil. Para tanto, dois experimentos são implementados. O primeiro trata especificamente de uma reestruturação tributária para o Rio Grande do Sul em que um desconto de ICMS relativo a 1% da arrecadação total em um produto é financiado via aumento da alíquota efetiva dos demais. O experimento mostrou que mudanças na matriz tributária gaúcha não se mostram nem economicamente nem fiscalmente neutras, tanto no curto quanto no longo prazo. Esse tipo de simulação é fundamental para determinar o posicionamento do Estado no caso das rodadas de discussão no Confaz quanto à alocação dos produtos nas faixas de alíquotas pré-definidas pelo Senado, pois evidencia os efeitos de aumentar a alíquota em um determinado setor e reduzir em outro. O segundo experimento aplica a proposta da PEC nº 233/08, assumindo que a harmonização se dará através da assimilação da alíquota efetiva média vigente no País em ambas as regiões analisadas. Os resultados mostraram que a harmonização leva a um aumento relevante da alíquota efetiva média no Rio Grande do Sul, com impactos negativos sobre o PIB e o emprego, porém com aumento significativo da arrecadação (com resultados opostos no Restante do Brasil). No entanto, esse resultado em termos de receita do Estado tem seu efeito diminuído em virtude da mudança do regramento do regime de apropriação do ICMS. Ainda assim, mesmo que potencialmente menor, o resultado revela, no caso do Rio Grande do Sul, um incremento na arrecadação em comparação com a arrecadação corrente. No entanto, é provável que isso não se materialize integralmente em ganhos de caixa para o Estado, dado que a reforma prevê mecanismos de compensação entre “ganhadores” e “perdedores” com a reforma. A temporalidade e os próprios mecanismos da reforma não atentam para questões econômicas, mas apenas fiscais. Os resultados da análise de equilíbrio geral computável mostram que, para o Rio Grande de Sul, a reforma pode gerar efeitos perversos sobre a atividade econômica e sobre as finanças públicas se os mecanismos de compensação de receita exaurirem o potencial ganho fiscal identificado para o Rio Grande do Sul. Neste caso, o Rio Grande do Sul perderia duplamente no processo de reforma. / Changes in the tributary legislation have always brought deep discussions into politics and the academic field. This happens because changes in this matter promote the reallocation of production factors, altering the production of sectors and regions and, thus, the production of revenues collected by the governments. The latter, therefore, altered by two reasons: the variations of the tax rate and the ones of the tributary bases themselves. The Brazilian tributary system, along the years, has gone through constant reformulations trying to become more modern and adequate to the current economic and political conditions. However, nowadays, different from what had occurred in the past, it is not possible to provide reforms based on tax load, since it has already reached incompatible standards compared with the country’s development level. In this scenario, it is presented the PEC 233/08, the most recent proposal of tributary reform that tries to keep unchanged the current tax load level; it proposes, among other changes, relevant modifications in the ICMS (Value Added Tax – VAT) legislation. This project of constitutional amendment proposes a harmonic legislation of ICMS and the preservation of mixed system of appropriation of taxes between the origin and the destination, increasing significantly, however, the appropriation of the destination. As it is needed an empiric approach for discussions, this thesis, which had the objective to estimate the impact derived from this proposal of reform, used a interregional computable general equilibrium (ICGE) model named BMARIA-RS-TAX, (database 2004), that investigated the economic relations between Rio Grande do Sul and the rest of Brazil. In order to carry out this research two experiments are implemented. The first deals specifically with tributary restructuring for Rio Grande do Sul, in which 1% discount in the ICMS total revenue of one product is financed by the effective increase on other products tax rates. The experiment showed that the changes in the tributary model of Rio Grande do Sul were neither economically nor fiscally neutral in short and long term period. This kind of simulation is essential to determine the positioning of the state in the rounds of discussions at Confaz as for allocating the products in the range of pre-determined tax rates by the Senate, because it shows evidences of increasing taxes in one specific sector and deceasing in another. The second experiment applied the proposal of PEC 233/08, assuming that the harmonization will be done through the assimilation of the current effective tax rate average in the country in both analyzed regions. The results showed the harmonization leads to a significant increase in the effective tax rate average in Rio Grande do Sul, which had negative impact in the GDP and employment rate; although, there were significant increases in the tax revenue collected in Rio Grande do Sul (the opposite results were also found for the rest of the country). However, in terms of revenue for the state, this result has its effects diminished due to the changing of rules of ICMS approval regime. Nevertheless, even being potentially smaller, the results show the increase in the revenues collection in comparison to the current revenue income. However, it is likely that this will not be materialized thoroughly in gains for the cash flow of the state, since the legislation provides mechanisms of compensation for ‘winners’ and ‘losers’ with the reform. The temporality and the reform’s own mechanisms do not draw attention to economic matters, but to fiscal ones. The result of the a interregional computable general equilibrium (ICGE) model analysis shows that, for Rio Grande do Sul, the reform can generate harsh results on the economic activities and on the public finances if mechanisms of income compensation blow over the potential of fiscal gains identified in Rio Grande do Sul. In this case, the state would lose twice in the process of reform.

Alterações na legislação tributária sempre motivaram profundas discussões políticas e acadêmicas. Isso ocorre pois mudanças dessa natureza promovem a realocação dos fatores de produção, alterando a produção de setores e regiões, e, consequentemente, da receita arrecadada pelos governos. Essa última, por sua vez, é alterada por duas motivações: as variações das alíquotas e as da própria base tributária. O sistema tributário brasileiro, ao longo do tempo, passou por constantes reformulações buscando torná-lo mais moderno e adequado às condições econômicas e políticas vigentes. Entretanto, atualmente, diferentemente do que ocorreu no passado, não é mais possível prover reformas tributárias lastreadas no aumento da carga, uma vez que essa já assume patamares incompatíveis com o grau de desenvolvimento do País. Nesse cenário, apresenta-se a PEC nº 233/08, a mais recente proposta de reforma tributária que, buscando manter inalterada a carga tributária no patamar atual, propõe, entre outras mudanças, modificações relevantes na legislação do ICMS. Esse projeto de emenda constitucional propõe a harmonização da legislação do ICMS e a preservação do sistema misto de apropriação do imposto entre origem e destino, aumentando significativamente, porém, a apropriação pelo destino. Dada a necessidade de uma abordagem empírica para as discussões, essa tese, com o objetivo de estimar os impactos decorrentes dessa proposta de reforma, utilizou um modelo de equilíbrio geral computável inter-regional denominado BMARIA- RS-TAX (ano-base 2004), que investigou as relações econômicas entre o Rio Grande do Sul e o Restante do Brasil. Para tanto, dois experimentos são implementados. O primeiro trata especificamente de uma reestruturação tributária para o Rio Grande do Sul em que um desconto de ICMS relativo a 1% da arrecadação total em um produto é financiado via aumento da alíquota efetiva dos demais. O experimento mostrou que mudanças na matriz tributária gaúcha não se mostram nem economicamente nem fiscalmente neutras, tanto no curto quanto no longo prazo. Esse tipo de simulação é fundamental para determinar o posicionamento do Estado no caso das rodadas de discussão no Confaz quanto à alocação dos produtos nas faixas de alíquotas pré-definidas pelo Senado, pois evidencia os efeitos de aumentar a alíquota em um determinado setor e reduzir em outro. O segundo experimento aplica a proposta da PEC nº 233/08, assumindo que a harmonização se dará através da assimilação da alíquota efetiva média vigente no País em ambas as regiões analisadas. Os resultados mostraram que a harmonização leva a um aumento relevante da alíquota efetiva média no Rio Grande do Sul, com impactos negativos sobre o PIB e o emprego, porém com aumento significativo da arrecadação (com resultados opostos no Restante do Brasil). No entanto, esse resultado em termos de receita do Estado tem seu efeito diminuído em virtude da mudança do regramento do regime de apropriação do ICMS. Ainda assim, mesmo que potencialmente menor, o resultado revela, no caso do Rio Grande do Sul, um incremento na arrecadação em comparação com a arrecadação corrente. No entanto, é provável que isso não se materialize integralmente em ganhos de caixa para o Estado, dado que a reforma prevê mecanismos de compensação entre “ganhadores” e “perdedores” com a reforma. A temporalidade e os próprios mecanismos da reforma não atentam para questões econômicas, mas apenas fiscais. Os resultados da análise de equilíbrio geral computável mostram que, para o Rio Grande de Sul, a reforma pode gerar efeitos perversos sobre a atividade econômica e sobre as finanças públicas se os mecanismos de compensação de receita exaurirem o potencial ganho fiscal identificado para o Rio Grande do Sul. Neste caso, o Rio Grande do Sul perderia duplamente no processo de reforma. / Changes in the tributary legislation have always brought deep discussions into politics and the academic field. This happens because changes in this matter promote the reallocation of production factors, altering the production of sectors and regions and, thus, the production of revenues collected by the governments. The latter, therefore, altered by two reasons: the variations of the tax rate and the ones of the tributary bases themselves. The Brazilian tributary system, along the years, has gone through constant reformulations trying to become more modern and adequate to the current economic and political conditions. However, nowadays, different from what had occurred in the past, it is not possible to provide reforms based on tax load, since it has already reached incompatible standards compared with the country’s development level. In this scenario, it is presented the PEC 233/08, the most recent proposal of tributary reform that tries to keep unchanged the current tax load level; it proposes, among other changes, relevant modifications in the ICMS (Value Added Tax – VAT) legislation. This project of constitutional amendment proposes a harmonic legislation of ICMS and the preservation of mixed system of appropriation of taxes between the origin and the destination, increasing significantly, however, the appropriation of the destination. As it is needed an empiric approach for discussions, this thesis, which had the objective to estimate the impact derived from this proposal of reform, used a interregional computable general equilibrium (ICGE) model named BMARIA-RS-TAX, (database 2004), that investigated the economic relations between Rio Grande do Sul and the rest of Brazil. In order to carry out this research two experiments are implemented. The first deals specifically with tributary restructuring for Rio Grande do Sul, in which 1% discount in the ICMS total revenue of one product is financed by the effective increase on other products tax rates. The experiment showed that the changes in the tributary model of Rio Grande do Sul were neither economically nor fiscally neutral in short and long term period. This kind of simulation is essential to determine the positioning of the state in the rounds of discussions at Confaz as for allocating the products in the range of pre-determined tax rates by the Senate, because it shows evidences of increasing taxes in one specific sector and deceasing in another. The second experiment applied the proposal of PEC 233/08, assuming that the harmonization will be done through the assimilation of the current effective tax rate average in the country in both analyzed regions. The results showed the harmonization leads to a significant increase in the effective tax rate average in Rio Grande do Sul, which had negative impact in the GDP and employment rate; although, there were significant increases in the tax revenue collected in Rio Grande do Sul (the opposite results were also found for the rest of the country). However, in terms of revenue for the state, this result has its effects diminished due to the changing of rules of ICMS approval regime. Nevertheless, even being potentially smaller, the results show the increase in the revenues collection in comparison to the current revenue income. However, it is likely that this will not be materialized thoroughly in gains for the cash flow of the state, since the legislation provides mechanisms of compensation for ‘winners’ and ‘losers’ with the reform. The temporality and the reform’s own mechanisms do not draw attention to economic matters, but to fiscal ones. The result of the a interregional computable general equilibrium (ICGE) model analysis shows that, for Rio Grande do Sul, the reform can generate harsh results on the economic activities and on the public finances if mechanisms of income compensation blow over the potential of fiscal gains identified in Rio Grande do Sul. In this case, the state would lose twice in the process of reform.

Introductory part of my thesis is aimed to describe the flat tax theory, its functioning and basic ideas of its presence as was described at the most elementary level by Robert Hall and Alvin Rabushka, American economists from Stanford{\crq}s University. I further describe reasons of the flat tax implementation in Slovakian environment because we used to share same cultural, political and economic history with this state. In the following passage of my thesis I analyzed a participation of particular taxes on Czech Republic{\crq}s public revenue budget. Next I defined the flat tax concepts including its rates introduced by the leading political parties of Czech Republic. I worked on a predictability of the tax revenue development when the flat tax is effective, while applied to model families. In the final capture I described the possible flat tax implementation impact on public budgets deficit financing in Czech Republic.

Alterações na legislação tributária sempre motivaram profundas discussões políticas e acadêmicas. Isso ocorre pois mudanças dessa natureza promovem a realocação dos fatores de produção, alterando a produção de setores e regiões, e, consequentemente, da receita arrecadada pelos governos. Essa última, por sua vez, é alterada por duas motivações: as variações das alíquotas e as da própria base tributária. O sistema tributário brasileiro, ao longo do tempo, passou por constantes reformulações buscando torná-lo mais moderno e adequado às condições econômicas e políticas vigentes. Entretanto, atualmente, diferentemente do que ocorreu no passado, não é mais possível prover reformas tributárias lastreadas no aumento da carga, uma vez que essa já assume patamares incompatíveis com o grau de desenvolvimento do País. Nesse cenário, apresenta-se a PEC nº 233/08, a mais recente proposta de reforma tributária que, buscando manter inalterada a carga tributária no patamar atual, propõe, entre outras mudanças, modificações relevantes na legislação do ICMS. Esse projeto de emenda constitucional propõe a harmonização da legislação do ICMS e a preservação do sistema misto de apropriação do imposto entre origem e destino, aumentando significativamente, porém, a apropriação pelo destino. Dada a necessidade de uma abordagem empírica para as discussões, essa tese, com o objetivo de estimar os impactos decorrentes dessa proposta de reforma, utilizou um modelo de equilíbrio geral computável inter-regional denominado BMARIA- RS-TAX (ano-base 2004), que investigou as relações econômicas entre o Rio Grande do Sul e o Restante do Brasil. Para tanto, dois experimentos são implementados. O primeiro trata especificamente de uma reestruturação tributária para o Rio Grande do Sul em que um desconto de ICMS relativo a 1% da arrecadação total em um produto é financiado via aumento da alíquota efetiva dos demais. O experimento mostrou que mudanças na matriz tributária gaúcha não se mostram nem economicamente nem fiscalmente neutras, tanto no curto quanto no longo prazo. Esse tipo de simulação é fundamental para determinar o posicionamento do Estado no caso das rodadas de discussão no Confaz quanto à alocação dos produtos nas faixas de alíquotas pré-definidas pelo Senado, pois evidencia os efeitos de aumentar a alíquota em um determinado setor e reduzir em outro. O segundo experimento aplica a proposta da PEC nº 233/08, assumindo que a harmonização se dará através da assimilação da alíquota efetiva média vigente no País em ambas as regiões analisadas. Os resultados mostraram que a harmonização leva a um aumento relevante da alíquota efetiva média no Rio Grande do Sul, com impactos negativos sobre o PIB e o emprego, porém com aumento significativo da arrecadação (com resultados opostos no Restante do Brasil). No entanto, esse resultado em termos de receita do Estado tem seu efeito diminuído em virtude da mudança do regramento do regime de apropriação do ICMS. Ainda assim, mesmo que potencialmente menor, o resultado revela, no caso do Rio Grande do Sul, um incremento na arrecadação em comparação com a arrecadação corrente. No entanto, é provável que isso não se materialize integralmente em ganhos de caixa para o Estado, dado que a reforma prevê mecanismos de compensação entre “ganhadores” e “perdedores” com a reforma. A temporalidade e os próprios mecanismos da reforma não atentam para questões econômicas, mas apenas fiscais. Os resultados da análise de equilíbrio geral computável mostram que, para o Rio Grande de Sul, a reforma pode gerar efeitos perversos sobre a atividade econômica e sobre as finanças públicas se os mecanismos de compensação de receita exaurirem o potencial ganho fiscal identificado para o Rio Grande do Sul. Neste caso, o Rio Grande do Sul perderia duplamente no processo de reforma. / Changes in the tributary legislation have always brought deep discussions into politics and the academic field. This happens because changes in this matter promote the reallocation of production factors, altering the production of sectors and regions and, thus, the production of revenues collected by the governments. The latter, therefore, altered by two reasons: the variations of the tax rate and the ones of the tributary bases themselves. The Brazilian tributary system, along the years, has gone through constant reformulations trying to become more modern and adequate to the current economic and political conditions. However, nowadays, different from what had occurred in the past, it is not possible to provide reforms based on tax load, since it has already reached incompatible standards compared with the country’s development level. In this scenario, it is presented the PEC 233/08, the most recent proposal of tributary reform that tries to keep unchanged the current tax load level; it proposes, among other changes, relevant modifications in the ICMS (Value Added Tax – VAT) legislation. This project of constitutional amendment proposes a harmonic legislation of ICMS and the preservation of mixed system of appropriation of taxes between the origin and the destination, increasing significantly, however, the appropriation of the destination. As it is needed an empiric approach for discussions, this thesis, which had the objective to estimate the impact derived from this proposal of reform, used a interregional computable general equilibrium (ICGE) model named BMARIA-RS-TAX, (database 2004), that investigated the economic relations between Rio Grande do Sul and the rest of Brazil. In order to carry out this research two experiments are implemented. The first deals specifically with tributary restructuring for Rio Grande do Sul, in which 1% discount in the ICMS total revenue of one product is financed by the effective increase on other products tax rates. The experiment showed that the changes in the tributary model of Rio Grande do Sul were neither economically nor fiscally neutral in short and long term period. This kind of simulation is essential to determine the positioning of the state in the rounds of discussions at Confaz as for allocating the products in the range of pre-determined tax rates by the Senate, because it shows evidences of increasing taxes in one specific sector and deceasing in another. The second experiment applied the proposal of PEC 233/08, assuming that the harmonization will be done through the assimilation of the current effective tax rate average in the country in both analyzed regions. The results showed the harmonization leads to a significant increase in the effective tax rate average in Rio Grande do Sul, which had negative impact in the GDP and employment rate; although, there were significant increases in the tax revenue collected in Rio Grande do Sul (the opposite results were also found for the rest of the country). However, in terms of revenue for the state, this result has its effects diminished due to the changing of rules of ICMS approval regime. Nevertheless, even being potentially smaller, the results show the increase in the revenues collection in comparison to the current revenue income. However, it is likely that this will not be materialized thoroughly in gains for the cash flow of the state, since the legislation provides mechanisms of compensation for ‘winners’ and ‘losers’ with the reform. The temporality and the reform’s own mechanisms do not draw attention to economic matters, but to fiscal ones. The result of the a interregional computable general equilibrium (ICGE) model analysis shows that, for Rio Grande do Sul, the reform can generate harsh results on the economic activities and on the public finances if mechanisms of income compensation blow over the potential of fiscal gains identified in Rio Grande do Sul. In this case, the state would lose twice in the process of reform.

This paper examines one of the most controversial items of the new GOP tax bill, the Mortgage Interest Deduction. The paper seeks to identify which groups would feel the greatest financial burden if the deduction is limited in the future tax code. The author identifies potential declines in mortgage interest rates and expensive home values as two key motivations behind the lobbying efforts for this deduction to remain untouched. Using data on mortgages originating in 2016, the author estimates a decline in mortgage interest rates between .039 and .043 percent for every $1,000 borrowed above the 2016 MID limits for taxpayers. The paper then goes on to discuss interest rate volatility implications for Mortgage Servicing Assets. The paper ends with a discussion on the downward pressure the new tax reform may have on expensive home values.

The purpose of the study is to analyse tax reform measures to secure the tax revenue base, in particular the personal income tax structure of South Africa. The main objectives are: firstly, to identify personal income tax reform interventions so as to align the personal income tax structure in South Africa with international best practices. Secondly, the impact of tax reforms on revenue collection, given optimal economic growth levels, is determined. Thirdly, to determine the best tax reform scenario which could minimise the individual tax burden and maximise its efficiency. Lastly, the impact of the suggested tax reforms on fairness as a principle of a good tax system is evaluated. A static micro-simulation model is developed from survey data and used to simulate the proposed tax reforms. Different tax reforms were selected from a study of international tax reform trends and an analysis of the South African personal income tax structure. The literature provides clear margins for the structuring of tax bands and threshold margins. Tax elasticities are estimated in order to explain the methodology for determining the impact of tax reforms. These elasticities include the elasticities for determining the progressiveness of the PIT structure, determining the deadweight loss (tax efficiency) and also to determine the optimal levels of taxes and economic growth and revenue maximisation. The different tax reform scenarios take the economy closer to or further away from optimum growth and optimum revenue. The results show that as far as marginal rates are concerned, a lowering in rates to levels on par with South Africa’s peers offers potential for improved levels of efficiency with the tax burden equal to or even below the optimal tax ratio from an economic growth point of view. Although such a ratio is below the optimal revenue ratio the results suggest that the loss in revenue could be minimised over time through a resultant increase in productivity and economic growth. By adjusting the non-taxable thresholds and taxable income bands according to the algorithm defined in the best practice scenario, more taxpayers will be included into the tax net but with a net decrease in tax liability. As a result the tax/GDP level also declines to a level below the optimal growth level but tax efficiency increases. The resultant loss in revenue will have to be recouped through increases in other than individual income taxes but improved levels of tax morality because of the lower margins for each tax band and increased productivity might also contribute to increased revenue performance. The tax structure is also more progressive which contributes towards the “fairness” of the tax regime. Regarding tax expenditure reforms, the analysis shows that medical tax credits offer a more equitable form of relief than medical deductions which substantiate this kind of reform as already implemented by government and which is to be fully phased in over the next couple of years. Tax liability is slightly lower in the case of medical credits compared to medical deductions but the difference is only marginal as far as net revenue and optimal growth and efficiency is concerned. However, a medical credit which increases disposable income at the lower end of the scale and discriminates against higher income groups also improves progressiveness of the tax regime and therefore the fairness thereof accordingly. Finally, the demographic impact of the suggested reforms also shows some important trends. Better education improves skills levels which seems to be positively correlated to taxable income levels. As far as age is concerned, the analysis shows that a substantial number of taxpayers in the categories below the age of 24 and above 65 fall within the lower taxable income groups. Those are also the most vulnerable groups from a subsistence point of view. Thus, tax reform that specifically improves their levels of disposable income should be prioritised in order to address equity and fairness as objectives for a “good” tax structure. / Thesis (PhD)--University of Pretoria, 2014. / gm2014 / Economics / Unrestricted

The study is concerned with reforms of tax systems in the european countries and possibilities of tax system optimalization. The research by the help of comparing analysis is applied to selected EU countries where in tax systems has been obtained integration and convergency trend in last decades. This has been one of the reasons for choosing this region. The selected countries have been chosen because they represent the greatest european countries and the most remarkable economics and/or experienced more significant tax reform. The object of study is to classify the reforms in individual countries according to the diversity of historical, economical and institutional progress and enquire their course and influence on the tax system structure. The analysis affords comparative and economically oriented view of tax systems in selected european countries and on the basis of specific criteria leads into the similar and dissimilar tax reform trends formulation .