本研究從長時間來觀察台灣香菸稅捐的累退程度變化，並且同時觀察台灣吸菸家庭具備何種特徵，以作為政府相關單位在制定租稅及菸害防制等政策的一個參考。利用行政主計處之「家庭收支調查報告」、台灣省菸酒公賣局之「臺灣地區菸酒事業統計年報」及學者研究等資料來進行累退性衡量，發現自1979年開始至2007年，我國香菸稅累退程度呈現加劇的情形，而各吸菸家庭則呈現出菸草消費支出金額愈高者戶長及家庭成員平均年齡愈低、教育程度較低、以及女性戶長比例下降等特徵。 由此結果可看出我國香菸稅累退程度並未減輕，低所得家庭反而較高所得家庭負擔為重，此外菸草消費支出較高的家庭由於平均教育程度較低，普遍缺乏吸菸會造成健康危害的風險認知，因此衛生醫療主管當局應加強菸害防制教育以利提升國民健康。 / This study observes the regressivity changes of cigarette taxation in Taiwan for long run and the features of smoking families in Taiwan to offer the government and relevant organization a reference in making taxation and tobacco hazards prevention policies. This study uses “Report on the Survey of Family Income and Expenditure in Taiwan Area of Republic of China” from 1979 to 2007, “Taiwan Tobacco and Wine Statistical Yearbook” and other scholars’ contribution to measure the regressivity of cigarette taxation. The results shows the regressivity of cigarette taxation in Taiwan is more and more severe from 1979 to 2007, and the smoking families which have higher tobacco expenditure shows the features of lower average age, lower education level, and lower percentage of female household head. This study concludes that the regressivity of cigarette taxation is more amd more severe, so the tax burden of lower income families is much serious than higher income families, and because of lower education level, the families with higher tobacco expenditure are popularly lack of risk perception which smoking hazards health. Therefore health and medical executive should reinforce tobacco prevention education to promote national health.

臺灣菸品市場之租稅負擔是個很奇特之現象，當臺灣政府對香菸產品課稅時，菸商會將租稅完全轉嫁給消費者，即便消費者之需求是有彈性的。本文為探討此原因，以Milgrom and Roberts之利潤目標模型為基礎，建立一個廠商追求利潤目標之模型來解釋，當菸商面臨政府課稅時，是否會將租稅百分之百轉嫁給消費者。由此模型推論出，若菸商欲維持市場之獨占或寡占地位時，便會追求較低之利潤目標，使潛在競爭者相信菸品市場利潤不大，此時潛在競爭者便不會進入菸品市場中與現有之菸商競爭。 本文設定利潤模型後，便以此利潤模型進行比較靜態分析，本文假設當菸商欲維持在市場之獨占或寡占地位時，於政府課徵從量稅後，會如何轉嫁租稅給消費者，並分別由價格及數量為切入點分析。經過比較分析後的結果可得知，只要菸商之目標為持續保有獨占或寡占之地位，而非追求利潤極大化時，租稅的完全轉嫁即會存在，即使消費者需求是有彈性的，消費者將會面對一個稅額百分之百增加的供給價格。 / The tax burden of cigarette products in the Taiwanese market baffles many researchers in public finance. Despite that the demand of cigarette products is elastic, when the tax rate of cigarette products increases, cigarette manufacturers, with no exception, raise the prices accordingly, and therefore, the increased taxes are entirely shifted to consumers. This is very different from the traditional idea of tax incidence based on elasticity. In order to figure out the reason, this paper uses the framework of the limit pricing model of Milgrom and Roberts (1982) with the assumption of target profit to establish an economic reasoning of why the tax hikes in the cigarette products are one hundred percent shifted to consumers. This model infers that when cigarette manufacturers have entry deterrence in mind, they tend to pursue a lower profit target to keep potential competitors away. Given the framework and basic assumption from above, comparative statics of tax increases are done for both quantity and pricing games. The results suggest that when cigarette manufacturers are facing an increase in the unit tax rate of their products, it is typical that the incidence of the increased tax been no less than one hundred percent forward-shifted to consumers. The traditional theory of tax incidence by elasticity under the profit maximization firms does not apply here. The economic intuition is that in order to thwart entry, existing firms use the complete forward shifting of the tax increase as a bad signal of the profitability of the market to potential competitors.

本論文的研究目的，主要是從理論的探討與實證的研究出發，評估國內以香菸稅做為反菸工具時的可行性與適當性。 　　由於近些年來，在反菸團體大力地宣導吸菸有害健康的警訊之下，香菸似乎被貼上了罪惡的標籤，除了對人體健康有直接的危害之外，吸菸行為在醫療資源上的浪費與經濟成本上的損失更是不容忽視的問題。因此，除了一般性的租稅課徵之外，許多的學者都主張應再對香菸課以重稅，以期減少社會大眾的香菸消費量。不過在另一方面，亦有學者指出，目前在探討吸菸行為所引起的疾病成本或外部成本時，都忽略了外在環境的改變與其他因素的影響，而使得菸害成本有被高估的可能，因此反對重課香菸稅。其次，由於香菸稅基本上是屬於銷售稅的性質，因此在課稅之後，勢必會對經濟體系造成若干程度的影響，所以本文在理論探討的部分，除了分析香菸稅的理論依據之外，亦將課稅之後所可能產生的經濟效果做一分析與整理。 　　而在實證研究的部分，本文則利用主計處「個人所得分配調查報告」的原始電腦資料，以橫斷面與虛擬長期追蹤模型資料(pseudo panel data)分別估計國內的香菸需求函數。根據研究的結果顯示，國內的香菸價格彈性在-1.35~-1.56之間，表示當價格上升10%之後，香菸的消費量將減少13.5%~15.6%，可見以香菸稅做為反菸工具的效果相當地顯著。 　　總之，若政府的政策是以維護國民的健康而欲減少國內的香菸消費時，透過對香菸課稅的方式確實能達到「以價制量」的既定目標，而且其政策的效果相當地顯著。不過值得注意的是，香菸稅的課徵，雖然可達成上述的反菸政策效果，但卻也會造成租稅累退與超額負擔的發生；甚至由於菸害成本的高估現象，而使得香菸稅率有偏高的趨劫。因此，政府在訂定香菸稅的政策時，除了考慮價格效果之外，同時也必須平衡其所產生的經濟影響，如此才能訂出適當的稅率以充分反映與矯正外部成本的發生。因此，一個最適香菸稅率的決定，則是未來所必須面對的問題了。