The Wall Street Journal described the move as “an unusual move in a strong economy that may signal longer-term concerns about consumers’ financial health.”

Capital One Financial Corp. (COF) and Discover Financial Services (DFS) recently said they are now much more cautious in how they will handle credit limits.

“In so many ways, one can’t help but be struck by…just how good the economy [at] this point is,” Capital One Chief Executive Richard Fairbank said on the company’s earnings call. “And in some ways, it almost feels too good to be true.”

During the last financial downturn, card issuers slashed credit limits to avoid incurring new losses. Around 2015, many lenders began increasing limits as they courted more balances and interest income.

Meanwhile, a recent Reuters analysis of U.S. household data shows that the bottom 60 percent of income-earners have accounted for most of the rise in spending over the past two years even as the their finances worsened - a break with a decades-old trend where the top 40 percent had primarily fueled consumption growth.

With borrowing costs on the rise, inflation picking up and the effects of President Donald Trump’s tax cuts set to wear off, a negative shock - a further rise in gasoline prices or a jump in the cost of goods due to tariffs - could push those most vulnerable over the edge, some economists warn.

Economists say one symptom of financial strain was last year’s spike in serious delinquencies on U.S. credit card debt, which many poorer households use as a stop-gap measure. The $815-billion market is not big enough to rattle Wall Street, but could be an early sign of stress that might spread to other debt as the Fed continues its gradual policy tightening.

More borrowers have also been falling behind on auto loans, which helped bring leverage on non-mortgage household debt to a record high in the first quarter of this year.

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