Wall Street Journal commentator, Greg Ip, reviews Thomas Philippon’s forthcoming book, The Great Reversal: How America Gave Up On Free Markets. Ip describes a “growing mountain” of research on industry concentration in the U.S. and reports that Philippon concludes competition has declined over time, harming U.S. consumers.
In one example, Philippon points to air travel. He notes that concentration in the U.S. has increased rapidly—spiking since the Great Recession—while concentration in the EU has increased modestly. At the same time, Ip reports “U.S. airlines are now far more profitable than their European counterparts.” (Although it’s debatable whether a five percentage point difference in net profit margin is “far more profitable”).
On first impression, the figures fit nicely with the populist antitrust narrative: As concentration in the U.S. grew, so did profit margins. Closer inspection raises some questions, however.
For example, the U.S. airline industry had a negative net profit margin in each of the years prior to the spike in concentration. While negative profits may be good for consumers, it would be a stretch to argue that long-run losses are good for competition as a whole. At some point one or more of the money losing firms is going to pull the ripcord. Which raises the issue of causation.
Just looking at the figures from the WSJ article, one could argue that rather than concentration driving profit margins, instead profit margins are driving concentration. Indeed, textbook IO economics would indicate that in the face of losses, firms will exit until economic profit equals zero. Paraphrasing Alfred Marshall, “Which blade of the scissors is doing the cutting?”
While the concentration and profits story fits the antitrust populist narrative, other observations run contrary to Philippon’s conclusion. For example, airline prices, as measured by price indexes, show that changes in U.S. and EU airline prices have fairly closely tracked each other until 2014, when U.S. prices began dropping. Sure, airlines have instituted baggage fees, but the CPI includes taxes, fuel surcharges, airport, security, and baggage fees. It’s not obvious that U.S. consumers are worse off in the so-called era of rising concentration.
Regressing U.S. air fare price index against Philippon’s concentration information in the figure above (and controlling for general inflation) finds that if U.S. concentration in 2015 was the same as in 1995, U.S. airfares would be about 2.8% lower. That a 1,250 point increase in HHI would be associated with a 2.8% increase in prices indicates that the increased concentration in U.S. airlines has led to no significant increase in consumer prices.
Also, if consumers are truly worse off, one would expect to see a drop off or slow down in the use of air travel. An eyeballing of passenger data does not fit the populist narrative. Instead, we see airlines are carrying more passengers and consumers are paying lower prices on average.
While it’s true that low-cost airlines have shaken up air travel in the EU, the differences are not solely explained by differences in market concentration. For example, U.S. regulations prohibit foreign airlines from operating domestic flights while EU carriers compete against operators from other parts of Europe. While the WSJ’s figures tell an interesting story of concentration, prices, and profits, they do not provide a compelling case of anticompetitive conduct.
At issue is the growth in the incidence of common-ownership across firms within various industries. In particular, institutional investors with broad portfolios frequently report owning small stakes in a number of firms within a given industry. Although small, these stakes may still represent large block holdings relative to other investors. This intra-industry diversification, critics claim, changes the managerial objectives of corporate executives from aggressively competing to increase their own firm’s profits to tacitly colluding to increase industry-level profits instead. The reason for this change is that competition by one firm comes at a cost of profits from other firms in the industry. If investors own shares across firms, then any competitive gains in one firm’s stock are offset by competitive losses in the stocks of other firms in the investor’s portfolio. If one assumes corporate executives aim to maximize total value for their largest shareholders, then managers would have incentive to soften competition against firms with which they share common ownership. Or so the story goes (more on that in a later post.)
Elhague and Posner, et al., draw their motivation for new antitrust offenses from a handful of papers that purport to establish an empirical link between the degree of common ownership among competing firms and various measures of softened competitive behavior, including airline prices, banking fees, executive compensation, and even corporate disclosure patterns. The paper of most note, by José Azar, Martin Schmalz, and Isabel Tecu and forthcoming in the Journal of Finance, claims to identify a causal link between the degree of common ownership among airlines competing on a given route and the fares charged for flights on that route.
Measuring common ownership with MHHI
Azar, et al.’s airline paper uses a metric of industry concentration called a Modified Herfindahl–Hirschman Index, or MHHI, to measure the degree of industry concentration taking into account the cross-ownership of investors’ stakes in competing firms. The original Herfindahl–Hirschman Index (HHI) has long been used as a measure of industry concentration, debuting in the Department of Justice’s Horizontal Merger Guidelines in 1982. The HHI is calculated by squaring the market share of each firm in the industry and summing the resulting numbers.
The MHHI is rather more complicated. MHHI is composed of two parts: the HHI measuring product market concentration and the MHHI_Delta measuring the additional concentration due to common ownership. We offer a step-by-step description of the calculations and their economic rationale in an appendix to our paper. For this post, I’ll try to distill that down. The MHHI_Delta essentially has three components, each of which is measured relative to every possible competitive pairing in the market as follows:
A measure of the degree of common ownership between Company A and Company -A (Not A). This is calculated by multiplying the percentage of Company A shares owned by each Investor I with the percentage of shares Investor I owns in Company -A, then summing those values across all investors in Company A. As this value increases, MHHI_Delta goes up.
A measure of the degree of ownership concentration in Company A, calculated by squaring the percentage of shares owned by each Investor I and summing those numbers across investors. As this value increases, MHHI_Delta goes down.
A measure of the degree of product market power exerted by Company A and Company -A, calculated by multiplying the market shares of the two firms. As this value increases, MHHI_Delta goes up.
This process is repeated and aggregated first for every pairing of Company A and each competing Company -A, then repeated again for every other company in the market relative to its competitors (e.g., Companies B and -B, Companies C and -C, etc.). Mathematically, MHHI_Delta takes the form:
where the Ss represent the firm market shares of, and Betas represent ownership shares of Investor I in, the respective companies A and -A.
As the relative concentration of cross-owning investors to all investors in Company A increases (i.e., the ratio on the right increases), managers are assumed to be more likely to soften competition with that competitor. As those two firms control more of the market, managers’ ability to tacitly collude and increase joint profits is assumed to be higher. Consequently, the empirical research assumes that as MHHI_Delta increases, we should observe less competitive behavior.
And indeed that is the “blockbuster” evidence giving rise to Elhauge’s and Posner, et al.,’s arguments For example, Azar, et. al., calculate HHI and MHHI_Delta for every US airline market–defined either as city-pairs or departure-destination pairs–for each quarter of the 14-year time period in their study. They then regress ticket prices for each route against the HHI and the MHHI_Delta for that route, controlling for a number of other potential factors. They find that airfare prices are 3% to 7% higher due to common ownership. Other papers using the same or similar measures of common ownership concentration have likewise identified positive correlations between MHHI_Delta and their respective measures of anti-competitive behavior.
Problems with the problem and with the measure
We argue that both the theoretical argument underlying the empirical research and the empirical research itself suffer from some serious flaws. On the theoretical side, we have two concerns. First, we argue that there is a tremendous leap of faith (if not logic) in the idea that corporate executives would forgo their own self-interest and the interests of the vast majority of shareholders and soften competition simply because a small number of small stakeholders are intra-industry diversified. Second, we argue that even if managers were so inclined, it clearly is not the case that softening competition would necessarily be desirable for institutional investors that are both intra- and inter-industry diversified, since supra-competitive pricing to increase profits in one industry would decrease profits in related industries that may also be in the investors’ portfolios.
On the empirical side, we have concerns both with the data used to calculate the MHHI_Deltas and with the nature of the MHHI_Delta itself. First, the data on institutional investors’ holdings are taken from Schedule 13 filings, which report aggregate holdings across all the institutional investor’s funds. Using these data masks the actual incentives of the institutional investors with respect to investments in any individual company or industry. Second, the construction of the MHHI_Delta suffers from serious endogeneity concerns, both in investors’ shareholdings and in market shares. Finally, the MHHI_Delta, while seemingly intuitive, is an empirical unknown. While HHI is theoretically bounded in a way that lends to interpretation of its calculated value, the same is not true for MHHI_Delta. This makes any inference or policy based on nominal values of MHHI_Delta completely arbitrary at best.
We’ll expand on each of these concerns in upcoming posts. We will then take on the problems with the policy proposals being offered in response to the common ownership ‘problem.’
Spirit Airlines says a new federal regulation aimed at protecting consumers is forcing it to charge passengers an additional $2 for a ticket.
The fee, which Spirit calls the “Department of Transportation Unintended Consequences Fee,” has been added to each ticket effective immediately, according to Misty Pinson, a Spirit spokeswoman.
The new DOT regulation allows passengers to change flights within 24 hours of booking without paying a penalty. The airline says the regulation forces them to hold the seat for someone who may or may not want to fly. As a consequence, someone who really does want to fly wouldn’t be able to buy that seat because the airline is holding it for someone who might or might not end up taking it.
In short, DOT is requiring airlines to give consumers a real option to change their flight plans at zero cost within a 24 hour window. Spirit rightly recognizes that options have value. Not only is there a value to consumers in ‘buying’ such an option, there is a cost associated with providing the option; in this case, the opportunity cost of selling seats that may be held for someone that will exercise the option to cancel without a fee.
Obviously, DOT head Ray LaHood is unimpressed.
“This is just another example of the disrespect with which too many airlines treat their passengers,” Department of Transportation Secretary Ray LaHood said in an e-mailed statement. “Rather than coming up with new and unnecessary fees to charge their customers, airlines should focus on providing fair and transparent service — that’s what our common sense rules are designed to ensure.”
Perhaps Mr. LaHood doesn’t understand the concept of options and option value. The right, but not the obligation, to undertake an activity (particularly under pre-specified terms) is clearly an economic good. The very notion that DOT’s new regulation is touted as “consumer friendly” recognizes that it creates additional value for consumers. That is, it’s giving something away that is of value…a property right to change one’s mind at zero cost. However, it is disingenuous of Mr. LaHood to object to the idea that giving away value imposes a cost on the one providing the value (and I don’t mean the DOT, but the airlines who must honor the consumer’s exercise of the option).
A better solution might be to require airlines to explicitly offer the option of a no-penalty change within a 24-hour window. Then consumers could choose whether to pay the fee and airlines might discover the true market value of that option. Spirits’ $2 may be too high. More likely, it’s too low. Many airlines already do offer the option of a no-fee cancellation and the fare differential is much higher than $2, but that option typically has a much longer maturity…any time after booking up until departure. A shorter maturity window should command a lower option value.
Spirit Airlines may be the epitome of nickle-and-diming air travel consumers, something many consumers (myself included in some cases) don’t appreciate. However, there is no denying that Spirit understands the nature of options and their value. And there’s also no denying that, based on its stock price over the past year, Spirit is doing at least as well as industry leaders in providing consumers value for the options they choose. Perhaps instead of casting aspersions, Mr LaHood and his staff should invite Spirit to teach them about this fairly fundamental concept of options and option value rather than imposing regulations with so little regard for their true costs.