Perhaps Nomi Prins did not choose the title of her piece “The next financial crisis will be worse than the last.” But the idea that there is going to be another financial crisis in the center of the world economy in the near term even vaguely comparable in virulence to the GFC has, as we shall see, no basis in reality. The reason is straightforward. Financial crises are denouements of credit booms, not asset price booms—all credit booms are attended by asset price booms but not the other way around—and while there is certainly an asset price boom in global markets, there is no credit boom at the center of the world economy. The chances of a banking crisis are even more remote than credit indicators suggest because of the extraordinary surveillance of the balance sheets of global banks since the GFC. Even if all legal-regulatory innovations over the past decade—especially the tighter limits on capital ratios—are bull, the sheer fact of enhanced regulatory and independent balance sheet surveillance means that banks find it much more difficult to hide risks on and off their balance sheets.

We now have a good handle on the mechanics of financial booms and crises. Financial booms are banking expansions. Banks are special because, yes, they create money by lending. But do not let the Bank of England distract you. The issue is that the excess elasticity of bank balance sheets mechanically generates lending booms since bank assets are the liabilities of non-banks. As a rule, credit booms emerge from the mutually-reinforcing interaction of property prices and bank lending. As collateral values go up, more can be lent against the same property; in turn, greater lending pushes up property prices further. Credit booms show up in credit gap measures such as credit-to-GDP ratios. We also understand how credit booms end. The stock of outstanding debt lags behind credit gaps. Once the debt burden, which is a function of the stock of outstanding debt not credit growth, becomes intolerable, credit defaults puncture the boom and precipitate a financial crisis. That’s why the best predictors of financial crises are credit gaps and debt ratios.

Metropolitan banking is international. As the day progresses, the trading book of global banks passes from Hong Kong to London to New York. The transatlantic circuit is especially important. The mid-2000s financial boom was driven in large part by a transatlantic, European banking glut. In other words, there is good reason to believe that cross-border banking flows are a especially good barometer of the global financial cycle. I therefore decided to analyze the JEDH database on cross-border banking and debt flows.

I’ll probably have much more to report later. But here’s the basic picture. Figure 1 displays three variables; all standardized to have mean 0 and variance 1. “CoreFPC” is the first principal component of the cross-border flows of Japan, Germany, France, Italy, Netherlands, Norway, Sweden, Denmark, and Finland. Roughly speaking, it captures the common variation in the series. “G2” is the sum of the cross-border flows of the United Kingdom and the United States. “China” is the sum of the cross-border flows of China, Hong Kong, and Macau.

A few observations are in order. The tight coupling of Anglo-Saxon finance (“G2”) and the rest of the core (“coreFPC”) is manifest; thus allowing us to interpret either as providing a fair metric for the global financial cycle. We will use the former because (a) it is a tighter, more parsimonious definition; (b) it is applicable in more general settings in the sense that we can extend many macrofinancial variables back to the 19th century without changing our center countries. Hélène Rey’s notion of the global financial cycle—as the covariation of risk premia embedded in global asset prices—is less relevant to macrofinancial stability than our metric. Although banking expansions can be read off of asset prices, it is a noisier metric precisely because not all asset price booms are attended by real financial booms that end in tears. Cross-border banking flows provide a finer measure of banking gluts than the compression of risk premia because all lending booms are attended by cross-border banking flows and vice-versa.

This metric confirms what credit gaps and debt service ratios can tell us about the buildup of financial imbalances in the center of the world economy. Interestingly, by this metric the Chinese cycle seems to have turned. This was not clear when we looked the credit gap (Figure 2).

Finally, as a sanity check we look at the bond market. The slope of the yield curve is the best predictor of US recessions out there. When the yield curve inverts it heralds a recession in the near term. There is good reason for this. The inversion of the yield curve destroys banks’ net interest margins; forward-looking measures of banks’ net worth fall; banks respond by shedding assets; finally, the attendant fall in bank lending pushes the macroeconomy into recession—this is Adrian and Shin‘s risk-taking channel of monetary policy. The term spread has indeed compressed, but the yield curve is still upward-sloping.

Because the current asset price boom is unattended by a credit boom in the center of the world economy, the possibility of a financial crisis comparable to the GFC is remote. And despite the “age” of the expansion, a normal recession does not yet seem to be on the cards either.