Desigualdade de renda: Quão bom é o livro do Piketty?

Não deve ser mais novidade para ninguém que o livro do economista Thomas Piketty, Capital in the 21st Century, está sendo um sucesso de vendas -- no momento, é o segundo livro mais vendido da Amazon. Tampouco deve ser surpreendente que desde o seu lançamento em inglês, resenhas do livro apareçam diariamente na mídia vindo de vários lugares.

O frisson em torno do livro, dizem as resenhas, é compreensível: primeiro porque é um trabalho profundo, rigoroso e extenso de levantamento de dados; segundo porque fala de desigualdade de renda/riqueza e constrói um argumento de que essa desigualdade (porque há obviamente trocentas outras) é inerente ao funcionamento dos mercados; terceiro porque ele sugere um esquema progressivo de tributação global como mecanismo de correção de máquina de criação de desigualdade que seria uma economia de mercado em seu arranjo corrente. 

Um livro desses, vai obviamente ser um sucesso. Desenterra um tesouro acadêmico (dados ricos e um grande tema) e mexe com os corações de todo mundo ao longo de todo o espectro político: da direita porque comumente odeia a ideia de ter o patrimônio dos muito ricos confiscado pelo Estado para fins redistributivos; da esquerda porque no livro de Piketty encontra amparo intelectual para o quest da igualdade que, muitos diriam, é a bandeira mais importante de identificação comum dos grupos que nesse lado do espectro político se colocam -- pouco importando aí, sobretudo para os que não são economistas, que isso tenha vindo de um economista cujos trabalhos acadêmicos sobre o tema que precederam o livro estejam imersos no mainstream da economia,  e não nas franjas da disciplina onde, ao menos por ora (you never know...), se encontram os conceitos e as ferramentas teóricas de que costumam usar os que defendem menos desigualdade (de renda/riqueza, sobretudo, suponho) mesmo que ao custo de menos eficiência (muitos nem desconfiam que existe esse tradeoff, mas ele existe).

Resenhas

Esse pequeno blá-blá foi para introduzir a sugestão de três resenhas que julgo equilibradas e bem decentes sobre o livro do Piketty -- eu poderia ser mais superlativo sobre a qualidade dessas resenhas dentre as dezenas que li, mas prefiro que você chega o juíz disso, sem falar que hoje vejo beleza em fazer uso do understatement.

É claro que resenha tem sempre o risco de omitir detalhes importantes e inevitavelmente vai sofrer de algum viés. Mas quem não tem tempo ou a disciplina para ler um livro desse tamanho talvez aprecie essas resenhas. Com eu disse, elas são concisas e balanceadas -- o que não quer dizer elas não sejam críticas aos resultados do livro. Martin Feldesntein, por exemplo, faz críticas devastadoras sobre o tratamento dos dados e aponta uma série de "buracos" no argumento principal do Piketty (sobre a tendência crescente da desigualdade).

São três resenhas:

1. Resenha de Dani Rodrik (Institute for Advanced Studies) no Project Syndicate (texto em inglês aqui).

2. Resenha de Martin Feldenstein (Univ. of Harvard) no Wall Street Journal (texto em inglês aqui)

3. Resenha de Keneth Rogoff (Univ. of Harvard) no Project Syndicate (texto em inglês aqui)

Trechos dessas resenhas abaixo. 

Dani Rodrik:

For one thing, the book is hardly an easy read. It is almost 700 pages long (including the notes), and, though Piketty does not spend much time on formal theory, he is not beyond sprinkling an occasional equation or Greek letters throughout the text. Reviewers have made much of Piketty’s references to Honoré de Balzac and Jane Austen; yet the fact is that the reader will encounter mainly an economist’s dry prose and statistics, while the literary allusions are few and far between.

The economics profession’s response has not been uniformly positive. The book’s argument revolves around a number of accounting identities that relate saving, growth, and the return to capital to the distribution of wealth in a society. Piketty is very good at bringing these abstract relations to life by hanging real numbers on them and tracing their evolution over history. Nevertheless, these are relationships that are well known to economists.

Piketty’s pessimistic prognosis rests on a slight extension of this accounting framework. Under plausible assumptions – namely that the wealthy save enough – the ratio of inherited wealth to income (or wages) continues to increase as long as r, the average rate of return to capital, exceeds g, the growth rate of the economy as a whole. Piketty argues that this has been the historical norm, except during the tumultuous first half of the twentieth century. If that is what the future looks like, we are facing a dystopia in which inequality will rise to levels never before experienced.

Keneth Rogoff:

Reading Thomas Piketty’s influential new book Capital in the Twenty-First Century, one might conclude that the world has not been this unequal since the days of robber barons and kings. That is odd, because one might conclude from reading another excellent new book, Angus Deaton’s The Great Escape (which I recently reviewed), that the world is more equal than ever.

Which view is right? The answer depends on whether one looks only at countries individually or at the world as a whole. Though Piketty is right that returns to capital have increased in the last few decades, he is too dismissive of the wide-ranging debate among economists concerning the causes. For example, if the main driver is the massive influx of Asian labor into globalized trade markets, the growth model put forth by the Nobel laureate economist Robert Solow suggests that eventually capital stocks will adjust and the wage rate will rise. Retirements from an aging labor force will eventually drive up wages as well. If, on the other hand, labor’s share of income is falling because of the inexorable rise of automation, downward pressures on that share will continue, as I discussed in the context of artificial intelligence a few years ago.

Fortunately, there are much better ways to address rich-country inequality while still fostering long-term growth in demand for products from developing countries. For example, a shift to a relatively flat consumption tax (with a large deductible for progressivity) would be a far simpler and more effective way to tax past wealth accumulation, especially if citizens’ tax home can be linked to the locale where their income was earned.

There are many practical policies that can be adopted to reduce inequality, in addition to a progressive consumption tax. Focusing on the US, Jeffrey Frankel of Harvard University has suggested the elimination of payroll taxes for low-income workers, a cut in deductions for high-income workers, and higher inheritance taxes. Universal pre-school education would enhance long-term growth, as would a much greater emphasis on lifetime adult education (my addition), possibly via online courses. Carbon taxes would help mitigate global warming while raising considerable revenues.

In accepting Piketty’s premise that inequality matters more than growth, one needs to remember that many developing-country citizens rely on rich-country growth to help them escape poverty. The first problem of the twenty-first century remains to help the dire poor in Africa and elsewhere. By all means, the elite 0.1% should pay much more in taxes, but let us not forget that when it comes to reducing global inequality, the capitalist system has had an impressive three decades.

Martin Feldesntein:

Mr. Piketty's theoretical analysis starts with the correct fact that the rate of return on capital—the extra income that results from investing an additional dollar in plant and equipment—exceeds the rate of growth of the economy. He then jumps to the false conclusion that this difference between the rate of return and the rate of growth leads through time to an ever-increasing inequality of wealth and of income unless the process is interrupted by depression, war or confiscatory taxation. He advocates a top tax rate above 80% on very high salaries, combined with a global tax that increases with the amount of wealth to 2% or more.

His conclusion about ever-increasing inequality could be correct if people lived forever. But they don't. Individuals save during their working years and spend most of their accumulated assets during retirement. They pass on some of their wealth to the next generation. But the cumulative effect of such bequests is diluted by the combination of existing estate taxes and the number of children and grandchildren who share the bequests.

The result is that total wealth grows over time roughly in proportion to total income. Since 1960, the Federal Reserve flow-of-funds data report that real total household wealth in the U.S. has grown at 3.2% a year while the real total personal income calculated by the Department of Commerce grew at 3.3%.

The second problem with Mr. Piketty's conclusions about increasing inequality is his use of income-tax returns without recognizing the importance of the changes that have occurred in tax rules. Internal Revenue Service data, he notes, show that the income reported on tax returns by the top 10% of taxpayers was relatively constant as a share of national income from the end of World War II to 1980, but the ratio has risen significantly since then. Yet the income reported on tax returns is not the same as individuals' real total income. The changes in tax rules since 1980 create a false impression of rising inequality.