Made available in DSpace on 2010-04-20T20:18:33Z (GMT). No. of bitstreams: 0 Previous issue date: 1994-06-17T00:00:00Z / The end of the USSR and the knockdown of the social ist economies with the apparent triumph Df the market quest ion: was Marx wrong when he previewed the inviabil ity of the capitalism or can it still happen? The answer for this question depends on the examination of the behavior Df profit rate. If the profit rate presents a tendency to falI. was Marx right. This work aims to examine the behavior of the profit it presents empiricaI experiments of the northamerican economy. Most of them. the profit rate falls because of the a) increasing taxes. b) rise in the use of improductive labour and c) risin9 bargaining power of workers. On the second part. it foeuses the theoretic point of viewand assume that the entrepreneur has a rational behavior. Even so the profit rate can fall, since it presupposted i) perfect competition, ii) no decline of the real wage, iii) uncertainty and iv) capital intensiv technological progress. Lastly it tries to analise the anteriorly found hypothesis in the Brazilian economy, between 1956 and 1992. In this case the profit rate shows a soft fall because of the cyclical movements and the rising use of unproductive labour. These conclusions, however, need a statistical confirmation, then it was not possible to make a econometric test. / Talvez seja excesso de pessimismo crer que se inicia a derrocada final do capitalismo. O fato, porém, é que esse sistema vem se defrontando com problemas para os quais não há ainda soluções visíveis, como a questão do emprego, por exemplo. As taxas mundiais de desemprego são elevadas e a globalização da economia tende a reforçar o desemprego estrutural. Daí a preocupação do G-7, que tem analisado o tema recorrentemente. O objetivo do presente trabalho, consiste na análise do comportamento apresentado pela taxa de lucro. Para tanto, ela será pensada de acordo com a interpretação marxista. Isto envolve uma análise teórica e empírica. Qualquer tentativa de estimação de conceitos marxistas, porém, deve abordar a questão da transformação de valores em preços.