Bank study: Credit still crunched

September 13, 2012, 11:21 PM UTC

FORTUNE — Here’s another reason we need Ben Bernanke’s QE3: Lending remains weak.

In the most recent quarter bank deposits grew twice as fast as loans, according to a report from bank research firm SNL Financial, which looked at U.S. lending capacity. Banks typically make money by paying a low interest rate for deposits, and then lending that money out at higher rates to businesses or home buyers. Banks, though, still appear to be hanging onto more of those deposits than they usually do. The report shows that while the credit crunch may still be over, the hangover remains.

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Lending dropped in the first quarter of 2012, further stoking fears that we could be headed for a double dip recession. But in the second three months of the year, loan volume rebounded. That, along with some other positive economic data, led some to question whether we needed more stimulus from the Federal Reserve.

But the SNL report shows that while lending rebounded, the pace was still much weaker than it normally is, signaling there is still something in the economy that is restricting credit. At the end of the second quarter, U.S. banks had lent out an average of just 73% of their deposits. That is unsurprisingly down from four years – a period in which lending was probably too loose – when bank loans approached 100% of deposits.

But what is concerning is that lending, as a percentage of deposits, is also down from a year ago, when the figure was 75%. Most people assume that banks have continued to heal in the past year. The fact that percentage of loans to deposits is shrinking would suggest the opposite. Since 1996, according to SNL Financial, figure has on average been above 80%.

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Bernanke has said that one of the main goals of the Fed’s recent stimulus efforts is to boost lending. On Thursday, the Fed announced a new round of bond buying, so-called quantitative easing, which should cause interest rates to drop, and encourage borrowing.

But it’s not clear why lending remains weaker than usual, and whether Bernanke’s fix will work. Some people say individuals and businesses worried about the economy don’t want to borrow. But the Fed’s most recent survey of lending officers found that demand for loans continues to increase. Banks, though, are still less willing to approve loans than they were back in 2005.

Earlier this week, JPMorgan Chase CEO Jamie Dimon said that regulators are forcing banks to hang on to more cash than they need, which is curtailing lending. Bank profitability is lower than it has been in years. Some, including bond manager Bill Gross, have wondered whether lower interest rates will only cause banks to pull bank lending further.

Whatever the answer this seems clear: Credit crunches take a long time to straighten out.