piketty

*Capital and Ideology*, by Thomas Piketty

This book is more than 1000 pp., here are my impressions:

1. About 600 pp. of this book is a carefully done history of the accumulation and sometimes dissipation of wealth and property.  You can evaluate that material without reference to any particular set of political views.

2. At some point the book veers into partisan issues such as the wealth tax.  Many of those parts remain interesting, but it also becomes clear that Piketty is “out to lunch,” to wit (p.591):

To return to the Soviet attitude toward poverty, it is important to try to understand why the government took such a radical stance against all forms of private ownership of the means of production, no matter how small.  Criminalizing carters and food peddlers to the point of incarcerating them may seem absurd, but there was a certain logic to the policy.  Most important was the fear of not knowing where to stop.  If one began by authorizing private ownership of small businesses, would one be able to set limits?

I can think of a less naive explanation of Soviet attitudes toward the private sector.  Piketty also calls for “participatory socialism” (p.592), a dubious doctrine not to be confused with say Nordic social democracy.  For instance, Sweden (among other countries) seems to have fairly extreme wealth inequality.

3. The sentence “Real wages are much higher in America than in Western Europe” does not come easily to his pen.  Nor does “The United States is a remarkably successful innovator, let’s see what we can learn from that.”  Or even “Raising wages is more important than merely limiting inequality.”  Those seems to be banished thoughts in the Piketty intellectual universe.

4. The sections on Soviet and socialist experience can only be called “delusional.”  In his account, if only a few political decisions had gone the other way, the USSR might have ended up on a path similar to that of Norway (p.603 and thereabouts).

You know, maybe you think that the inequalities of the current day are much worse than people had been expecting.  but that should not revise your view of socialism and the Soviet Union, two matters fairly well settled by historical research.

5. Give these lenses, it is impossible for Piketty to offer any commentary on recent events (about the last 400 pp. of the book) that is anything other than distorted and unreliable.  There is massive distrust of the wealthy in this book, and virtually no distrust of concentrated state power.

6. There is a considerable sum of useful and valuable material in this book, and I would not try to dissuade anyone inclined from reading it.  Nonetheless I suspect its main import is as another sign of the growing compartmentalization of academic discourse — good work intermingled with highly questionable partisan material — and how so many academics, if the mood affiliation tilts in the right direction, will tolerate or even encourage that.

You can pre-order the book here.

Henry George, Swift, and Piketty go to the movies (premises discussed, but no spoilers)

Yes, I’m talking about Downsizing, starring Matt Damon.  If Henry George is right about exorbitant rents and land scarcity, of course the solution is to shrink the people, thereby creating in real terms more land (plus solving a lot of environmental problems).  In this movie, shrinking people to a few centimeters tall raises the value of a dollar by about 1000x — how’s that for a Georgist result?  The small people live in splendid houses, massive relative to their diminutive size, and can eat all the gourmet food they want because they need only a snippet of foie gras or for that matter a very small piece of diamond.  Yet they still must interact (badly) with the larger world, thus the Swift connection.  How about Piketty?  Well, the small people have trouble mastering nature or producing for the larger outside world, so they are dependent on their preexisting wealth.  The wealth to income ratio is remarkably high, and woe unto anyone who has to rely on labor income in the “small world.”

Then the movie starts!  It’s an uneven film in a number of ways, still for economics “food for thought,” or for that matter social critique, I haven’t seen anything nearly as good for a while.

Is Piketty’s Data Reliable?

When Thomas Piketty’s Capital in the Twenty-First Century first appeared many economists demurred on the theory but heaped praise on the empirical work. “Even if none of Piketty’s theories stands up,” Larry Summers argued, his “deeply grounded” and “painstaking empirical research” was “a Nobel Prize-worthy contribution”.

Theory is easier to evaluate than empirical work, however, and Phillip Magness and Robert Murphy were among the few authors to actually take a close look at Piketty’s data and they came to a different conclusion:

We find evidence of pervasive errors of historical fact, opaque methodological choices, and the cherry-picking of sources to construct favorable patterns from ambiguous data.

Magness and Murphy, however, could be dismissed as economic history outsiders with an ax to grind. Moreover, their paper was published in an obscure libertarian-oriented journal. (Chris Giles and Ferdinando Giugliano writing in the FT also pointed to errors but they could be dismissed as journalists.) The Magness and Murphy conclusions, however, have now been verified (and then some) by a respected figure in economic history, Richard Sutch.

I have never read an abstract quite like the one to Sutch’s paper, The One-Percent across Two Centuries: A Replication of Thomas Piketty’s Data on the Distribution of Wealth for the United States (earlier wp version):

This exercise reproduces and assesses the historical time series on the top shares of the wealth distribution for the United States presented by Thomas Piketty in Capital in
the Twenty-First Century….Here I examine Piketty’s US data for the period 1810 to 2010 for the top 10 percent and the top 1 percent of the wealth distribution. I conclude that Piketty’s data for the wealth share of the top 10 percent for the period 1870 to 1970 are unreliable.
The values he reported are manufactured from the observations for the top 1 percent inflated by a constant 36 percentage points. Piketty’s data for the top 1 percent of the distribution for the nineteenth century (1810–1910) are also unreliable. They are based
on a single mid-century observation that provides no guidance about the antebellum trend and only tenuous information about the trend in inequality during the Gilded Age. The values Piketty reported for the twentieth century (1910–2010) are based on more
solid ground, but have the disadvantage of muting the marked rise of inequality during the Roaring Twenties and the decline associated with the Great Depression. This article offers an alternative picture of the trend in inequality based on newly available data and a reanalysis of the 1870 Census of Wealth. This article does not question Piketty’s integrity.

You know it’s bad when a disclaimer like that is necessary. In the body, Sutch is even stronger. He concludes:

Very little of value can be salvaged from Piketty’s treatment of data from the nineteenth century. The user is provided with no reliable information on the antebellum trends in the wealth share and is even left uncertain about the trend for the top 10 percent during
the Gilded Age (1870–1916). This is noteworthy because Piketty spends the bulk of his attention devoted to America discussing the nineteenth-century trends (Piketty 2014: 347–50).

The heavily manipulated twentieth-century data for the top 1 percent share, the lack of empirical support for the top 10 percent share, the lack of clarity about the procedures used to harmonize and average the data, the insufficient documentation, and the spreadsheet errors are more than annoying. Together they create a misleading picture of the dynamics of wealth inequality. They obliterate the intradecade movements essential to an understanding of the impact of political and financial-market shocks on inequality. Piketty’s estimates offer no help to those who wish to understand the impact of inequality on “the way economic, social, and political actors view what is just and what is not” (Piketty 2014: 20).

One of the reasons Piketty’s book received such acclaim is that it fed into concerns about rising inequality and it’s important to note that Sutch is not claiming that inequality hasn’t risen. Indeed, in some cases, Sutch argues that it has risen more than Piketty claims. Sutch is rather a journeyman of economic history upset not about Piketty’s conclusions but about the methods Piketty used to reach those conclusions.

Piketty, Housing, and Capital Share

Gianni La Cava has a very interesting article (based on a longer paper) on what accounts for the rising share of capital in the income accounts:

A key observation in Thomas Piketty’s Capital in the Twenty-First Century (Piketty 2014) is that the share of aggregate income accruing to capital in the US has been rising steadily in recent decades. The growing disparity between the income going to wage earners and capital owners has led to calls for government intervention. But for such interventions to be effective, it is important to ask who the capital owners are.

Recent research has shown that the long-run rise in the net capital income share is mainly due to the housing sector (e.g. Rognlie 2015, Torrini 2016 – see Figure 1). This phenomenon is not specific to the US but has been evident in almost every advanced economy. This suggests that it is not entrepreneurs and venture capitalists that are taking an increasing share of the economy, but land owners.

…The decomposition of the national accounts by type of housing indicates that the secular rise is mainly due to a rising share of imputed rent going to owner-occupiers. The owner-occupier share of aggregate income has risen from just under 2% in 1950 to close to 5% in 2014 (top panel of Figure 2). The share of income going to landlords (i.e. market rent) has also doubled in the post-war era. But, in aggregate, the effect of imputed rent is larger simply because there are nearly twice as many home owners as renters in the US economy. A similar phenomenon is observed in the personal consumption expenditure data (bottom panel of Figure 2). In other words, today’s landed gentry are predominantly home owners, not private landlords.

…The geographic decomposition reveals that the long-run rise in the housing capital income share is fully concentrated in states that face housing supply constraints. To see this, I divide the states into ‘elastic’ and ‘inelastic’ groups based on whether the state is above or below the median housing supply elasticity index (as measured by Saiz 2010). This index captures both geographical and regulatory constraints on home building across different US regions. For 50 years, the share of total housing capital income going to the supply-elastic states has been unchanged at about 3% of GDP (Figure 3). In contrast, the share going to the supply-inelastic states has risen from around 5% in the 1960s to 7% of GDP more recently. Notably, these divergent trends in housing capital income are not due to a few ‘outlier’ states where housing supply is particularly constrained, such as New York or California – instead, there is a clear negative correlation between the long-run growth in housing capital income and the extent to which housing supply is constrained across all states (Figure 4).

Kenneth Arrow on Piketty

Here is the closing paragraph of his short but interesting piece:

We might be especially moved to consider a consumption tax if we consider that Piketty’s proposed wealth tax seems in any case to be much higher than it sounds. If we are to assume, say a 5% return on property, then a 2% per annum tax on wealth would amount to about 40% of property income. If investment is financed by property income, this implies a very considerable reduction in investment. Is this desirable? One might doubt it, especially since the effects on investment would be substantial, even apart from incentive effects, which might also be quite considerable.

I would stress that a capital gains tax — not indexed for inflation — shares many properties of a wealth tax.  In recent academic debates, this point about wealth taxes is not being made nearly enough.

Matt Rognlie on Piketty, net capital returns, and housing

Brookings emails me:

Capital income is not growing unboundedly at the expense of labor, and further accumulation of capital in fact most likely means a fall in capital’s share of total income – refuting one of the main theories of economist Thomas Piketty’s popular book Capital in the 21st Century — according to a paper presented today at the Spring 2015 Conference on the Brookings Papers on Economic Activity (BPEA).

Existing studies that show an increase in capital’s share of income miss the growing role of depreciation in short-lived capital, in items such as software, says MIT’s Matthew Rognlie in “Deciphering the Fall and Rise in the Net Capital Share.”  Rognlie subtracts depreciation in seven large developed economies (the US, Japan, Germany, France, the UK, Italy, and Canada) to get net capital income, and finds that the only long-term rise in capital’s share of income is in housing. Capital income elsewhere in the economy has grown moderately, but it is only recovering from a large fall that lasted from 1948 through the 1970s.

Piketty’s Capital argues that the role of capital in the economy, after falling during the Depression and two world wars, is set to recover to the high levels of the 19th and early 20th centuries. According to Piketty, wealth will accumulate amid slowing economic growth to push up the capital-to-GDP ratio in the economy, which will then cause an increase in capital’s share of income — and growing inequality.

In contrast, Rognlie finds that a rising capital-to-GDP ratio is most likely to result in a fall in capital’s share of income, since the net rate of return on capital will fall by an even larger proportion than the capital-to-GDP ratio rises. Outside of housing, postwar changes in the value of the capital stock have not led to parallel changes in capital’s share of income. In fact, the value of the capital stock relative to private income reached its highs in the late 1970s and early 1980s, when capital’s share of income was near a low.

Rognlie shows that the share of net income generated by housing has risen in all seven large developed economies since data became available. “Housing’s central role in the long-term behavior of the aggregate net capital share has… not been emphasized elsewhere…Observers concerned about the distribution of income should keep an eye on housing costs,” he writes.

Brad DeLong offers comment.

Here Jim Tankersley has a superb profile of Rognlie and the story behind his comment, MR plays a role too.  Recommended.

Human capital, wealth, and Piketty’s calculations

David N. Weil has a new paper on this topic, and it makes some interesting points, here is one:

Net Social Security wealth of currently living Americans in 2013 was $12.9 trillion, or three quarters of a year’s GDP.

More generally he makes this point:

In 1700, at the beginning of the period that he studies in his book, marketable assets were indeed pretty much the only form of wealth.  But over the intervening 300 years, new types of wealth, most notably human capital and transfer wealth, have come to constitute a very significant fraction of total wealth.  Thus the constancy of the wealth/income ratio as portrayed in his data is an illusion.  More important, however, is the fact that the distribution of the new types of wealth that he does not measure is far more equal than, and not perfectly correlated with, wealth that falls into his analysis.

The paper is interesting throughout, the NBER version is here.  The top link here leads you go an ungated pdf.

Addendum: In a new essay Piketty responds to critics.

Thomas Piketty refuses France’s highest honor

France’s influential economist Thomas Piketty, author of “Capital in the 21st Century”, on Thursday refused to accept the country’s highest award, the Legion d’honneur, to criticise the Socialist government in power.

“I refuse this nomination because I do not think it is the government’s role to decide who is honourable,” Piketty told AFP.

“They would do better to concentrate on reviving (economic) growth in France and Europe,” added Piketty, who was once close to the Socialist Party but has distanced himself from the policies of President Francois Hollande.

The link is here, via many people in my Twitter feed, including Justin Wolfers and Claudia Sahm.  There is a bit more here.

Why has Piketty’s *Capital* sold so many copies?

There is a symposium in The Guardian on that question, here is my short contribution:

Thomas Piketty’s Capital in the Twenty-First Century has been a hit for several reasons, most notably the quality of the work. But I’d like to focus on a neglected reason why the book has found so much support, namely it appears to strengthen the case for redistribution.

Most previous commentators focused on income inequality. Bill Gates or JK Rowling have earned more than CEOs or authors in the past, while incomes in the middle class or lower middle classes are often stagnating below what previous generations could expect. That’s a labor market issue – namely that some individuals are not very much demanded by employers.

The obvious questions are then a) how can we make low-earners more productive, and also b) how can we improve education?

Perhaps most importantly, as these issues get processed by the public there is a common attitude – whether justified or not – that many of the lower earners are partially or fully responsible for their own plight. The egalitarians don’t tend to win these policy debates.

In the simplest version of the Piketty model, wealth grows more quickly than does the economy as a whole and thus the picture changes. The relative losers are no longer low earners but rather anyone who is not a capitalist. Any disparity is due not to their shortcomings in labor markets but rather to their lack of a high initial endowment.

Furthermore redistribution will work like a charm, at least provided the redistribution is enough to give the poorer individuals some capital to invest.

If you are an activist who favors lots of redistribution, the Piketty story is a lot easier to tell yourself and to tell your audiences – and that is yet another reason for its popularity.

The other contributions are by Brad DeLong, Stephanie Kelton, and Emanuel Derman, who cannot bring himself to read the book.

Acemoglu and Robinson on Piketty

There is a new paper out by them:

Thomas Piketty’s recent book, Capital in the Twenty First Century, follows in the tradition of the great classical economists, Malthus, Ricardo and Marx, in formulating “general” laws to diagnose and predict the dynamics of inequality. We argue that all of these general laws are unhelpful as a guide to understand the past or predict the future, because they ignore the central role of political and economic institutions in shaping the evolution of technology and the distribution of resources in a society. Using the economic and political histories of South Africa and Sweden, we illustrate not only that the focus on the share of top incomes gives a misleading characterization of the key determinants of societal inequality, but also that inequality dynamics are closely linked to institutional factors and their endogenous evolution, much more than the forces emphasized in Piketty’s book, such as the gap between the interest rate and the growth rate.

For the pointer I thank Nathaniel Bechhofer.

Peter Lindert on Piketty

He has an NBER review essay on the book.  Here is one bit:

Piketty’s “r > g” device, for all its amazing rhetorical power, does not take us very far. Our task of explaining and predicting inequality movements is not made any easier by the requirement that we must first predict both a “rate of return” and the growth rate of the economy. The formula r – g takes us no further than we were transported fifty years ago by the concept of total factor productivity as a “source” of growth. It will be another “measure of our ignorance.”

Here is more:

Oddly, however, for the twentieth century trends that he and his collaborators have documented so well, the relevance of the wealth/income and capital/income ratios for the income distribution is less compelling. Across countries, the levels and movements of this ratio do not correlate well with those in income inequality. Over time, there is more correlation, within Britain, or France, or Germany, or the United States. Yet, as we shall see later, the same overall movements will show up when we look at the inequality movements in incomes that have little to do with wealth, such as wage rates or in middle/lower income ratios.

The essay is interesting throughout and you will see at the end that Lindert is no friend of inequality and no enemy of highly progressive taxation.  By the way, here is a Lindert essay on three centuries of inequality in Britain and America (pdf).  Here is Lindert, with Williamson, on whether globalization makes the world more unequal.  He knows this area very well.

More Matt Rognlie on Piketty — the most important point

Matt has what is probably the single best, focused technical critique of Piketty.  Here are his concluding remarks:

Compared to the grand scope of Piketty (2014), the objective of this note has been quite narrow: to systematically explore the relevant evidence on diminishing returns to capital. Technical and uninspiring as this question may be, it is an essential step in knowing whether the prediction of rising capital income and inequality through accumulation—a prediction that gives Capital in the Twenty-First Century its title—will really come to pass. And given the evidence here that Piketty (2014) understates the role of diminishing returns, some skepticism is certainly in order.

But rejection of this specific mechanism does not constitute rejection of all Piketty (2014)’s themes. Inequality of labor income, for instance, is a very different issue—one that remains valid and important. Capital itself remains an important topic of study. Among large developed economies, the remarkably consistent trend toward rising capital values and income is undeniable. As Sections 3.3 and 3.4 establish, this trend is a story of rising capital prices and the ever greater cost of housing—not the secular accumulation emphasized in Capital — but it has distributional consequences all the same. Policymakers would do well to keep this in mind.

The full piece is here (pdf), excellent and on target throughout.

To be perfectly frank on this one, Matt here is completely correct and Piketty has not produced any effective response to this point, either within the book or without.  The internal response “I still think we need to worry about inequality therefore I side with Piketty” simply represents a misunderstanding of Matt’s argument.  Piketty’s mechanism of accumulation, as laid out in his book, is simply the wrong mechanism for understanding growing inequality, both theoretically and empirically.  And it is a shame that the Giles critique from the FT has attracted so much attention because it has distracted everyone from the more serious problems with the argument of the book.

Piketty v. Solow

Krusell and Smith lay out the Solow and Piketty growth models very nicely but perhaps not in a way that is immediately transparent if you are not already familiar with growth models. Thus, in this note I want to lay out the differences using the Super Simple Solow model that Tyler and I developed in our textbook. The Super Simple Solow model has no labor growth and no technological growth. Investment, I, is equal to a constant fraction of output, Y, written I=sY.

Capital depreciates–machines break, tools rust, roads develop potholes. We write D(epreciation)=dK where d is the rate of depreciation and K is the capital stock.

Now the model is very simple. If I>D then capital accumulates and the economy grows. If I<D then the economy shrinks. Steady state is when I=D, i.e. when we are investing just enough each period to repair and maintain the existing capital stock.

Steady state is thus when sY=dK so we can solve for the steady state ratio of capital to output as K/Y=s/d. I told you it was simple.

Now let’s go to Piketty’s model which defines output and savings in a non-standard way (net of depreciation) but when written in the standard way Piketty’s saving assumption is that I=dK + s(Y-dK). What this means is that people look around and they see a bunch of potholes and before consuming or doing anything else they fill the potholes, that’s dK. (If you have driven around the United States recently you may already be questioning Piketty’s assumption.) After the potholes have been filled people save in addition a constant proportion of the remaining output, s(Y-dk), where s is now the Piketty savings rate.

Steady state is found exactly as before, when I=D, i.e. dK+s(Y-dK)=dK or sY=sdK which gives us the steady level of capital to output of K/Y=s/(s d).

Now we have two similar looking expressions for K/Y, namely s/d for Solow and s/(s d) for Piketty. We can’t yet test which is correct because nothing requires that the two savings rates be the same. To get further suppose that we now allow Y to grow at rate g holding K constant, that is over time because of better technology we get more Y per unit of K. Since Y will be larger the intuition is that the equilibrium K/Y ratio will be lower, holding all else the same. And indeed when you run through the math (hand waving here) you get expressions for the Solow and Piketty K/Y ratios of s/(g+d) and s/(g+sd) respectively, i.e. a simple addition of g to the denominator in both cases (again bear in mind that the two s’s are different.)

We can now see what the models predict when g changes–this is a key question because Piketty argues that a fall in g (which he predicts) will greatly increase K/Y. Here is a table showing how K/Y changes with g in the two models. I assume for both models that d=.05, for Solow I have assumed s=.3 and for Piketty I have calibrated so that the two models produce the same K/Y ratio of 3.75 when g=.03 this gives us a Piketty s=.138.

SolowPiketty

As g falls Piketty predicts a much bigger increase in the K/Y ratio than does Solow. In Piketty’s model as g falls from .03 to .01 the capital to output ratio more than doubles! In the Solow model, in contrast, the capital to output ratio increases by only a third. Remember that in Piketty it’s the higher capital stock plus a more or less constant r that generates the massive increase in income inequality from capital that he is predicting. Thus, the savings assumption is critical.

I’ve already suggested one reason why Piketty’s saving assumption seems too strong–Piketty’s assumption amounts to a very strong belief that we will always replace depreciating capital first. Another way to see this is to ask where does the extra capital come from in the Piketty model compared to Solow? Well the flip side is that Solow predicts more consumption than Piketty does. In fact, as g falls in the Piketty model so does the consumption to output ratio. In short, to get Piketty’s behavior in the Solow model we would need the Solow savings rate to increase as growth falls.

Krusell and Smith take this analysis a few steps further by showing that Piketty’s assumptions about s are not consistent with standard maximizing behavior (i.e. in a model in which s is allowed to vary to maximize utility) nor do they appear consistent with US data over the last 50 years. Neither test is definitive but both indicate that to accept the Piketty model you have to abandon Solow and place some pretty big bets on a non-standard assumption about savings behavior.