Understanding Piketty, Part 2

by: The Angry Bear

By Kenneth Thomas

In my last post, I gave an introduction to the massive data work underlying Capital in the Twenty-First Century, as well as two clear results from Piketty's work. First, he showed that the optimistic Kuznets view after World War II that inequality was well on its way to being conquered was wrong, based on putting too much stock into a short-term trend. Inequality in fact has been increasing in the industrialized world since about 1980. Second, Piketty showed that a slow-growth economy is ripe for an increasing concentration of wealth in society, absent government action to counter that trend. He introduced the relationship r>g, which says the private return on capital is greater than the economic growth rate. When this holds true, as it has for most of history, inequality is likely to increase.

In this post, I address Part Two, "The Dynamics of the Capital/Income Ratio." The next two posts will address parts Three and Four, followed by a summation and critique of certain aspects of the book.

One important observation that Piketty makes is that in Europe, capital in the form of agricultural land accounted for 300-400% of gross national income (GNI), and total capital reached about 700% of GNI in the early 1700s. In Britain (Figure 3.1), France (Figure 3.2), and Germany (Figure 4.1), total capital fell below 300% of GNI in the period encompassing World War I and World War II. By 2010, total capital was back up to about 600% of GNI, but its composition had changed, with agricultural land falling to vanishingly low levels, replaced by housing and other domestic capital. In the United States (Figure 4.2), by contrast, farmland in 1770 was plentiful and cheap, making up about just 150% of GNI. Total capital also was much lower than in Europe, only about 300% of GNI. In the twentieth century, however, the U.S. did not suffer the devastation of the World Wars, so it had fewer and smaller dips in the value of total capital, which had risen to about 450% of national income in 2010; like in Europe, however, the value of U.S. agricultural land had also fallen to a tiny fraction of national income. Piketty points out if one includes the value of slaves, total U.S. capital in 1770-1810 rises by another 150% of national income (Figure 4.10), meaning that the capital/income ratio in the United States has been even more stable than it appears at first blush.

For Piketty, the resurgence of the capital/income ratio in the late 20th century is a consequence of slow growth. One important result of this is that capital's share of national income has increased since 1975, and labor's share has consequently fallen. According to his data for eight rich countries (the United States, the United Kingdom, Germany, Japan, France, Canada, Italy [the G-7, as they are usually called] and Australia.), "Capital income absorbs between 15 percent and 25 percent of national income in rich countries in 1970, and between 25 percent and 30 percent in 2000-2010″ (Figure 6.5, p. 222). Notably, he raises the important point, central to my own academic work, that the increasing mobility of capital increases capital's bargaining power vis-a-vis both labor and governments (p. 221). He considers it likely that this factor has been mutually reinforcing with the ability to substitute capital for labor. I would consider it not merely likely, but close to self-evident. Moreover, he omits (though I am sure he is aware) that one use capital mobility has been put to is to substitute less expensive for more expensive labor.

This increase in capital's share of national income shatters another comforting standard economic view, that the relative share of capital and labor is fixed. This assumption is built into a workhorse of neoclassical macroeconomic analysis, the Cobb-Davis production function. Piketty shows that, as with Kuznets work, the results of Cobb and Douglas generalize from a data sample that is far too short in term (p. 219).

My next post will analyze Part Three, "The Structure of Inequality."