The overall stock market was roughly flat today, and Bank of America (BAC 1.70%) has pretty much followed suit. But this isn't for lack of significant news.

Front and center was the advanced reading on fourth-quarter GDP, which showed a 0.1% drop. That's right, a drop. I don't want to say that shouldn't be somewhat worrisome, but when we dig deeper into the numbers, we can get some relief from the fact that much of the decline was driven by lower government spending even as businesses and consumers were spending more.

Breathe, breathe... OK, continue.

Dour sentiment driven by the GDP report may have also been offset by ADP's report on job growth for January. While the numbers from the government that most people tend to focus on come out later in the week, it's still worth noting that ADP's payroll tally was above both last month and this month's expectations.

OK, feeling better. Heart rate falling.

On balance, the above is probably good news for B of A. Business and consumer spending will drive more borrowing activity, while job growth could serve to further goose spending and borrowing. And though we hear so much about the complexity of B of A, its lifeblood is still lending to individuals and businesses.

However, before we get too comfortable, it's important that we consider the release from the Mortgage Bankers Association today as well. The group's weekly report on mortgage applications showed that on an adjusted basis (seasonally and for the Martin Luther King holiday), mortgage applications fell 8.1% last week from the week prior. The MBA's Refinance Index fell 10%.

Big deal? It could be. While lending margins have been falling, banks with robust mortgage practices have been raking in fees from loan originations -- particularly refinancings. A slowdown on that fee income would obviously be painful.

Mortgage market leaders Wells Fargo (WFC -0.26%) and JPMorgan (JPM 1.44%) are obviously exposed the most, here, from an absolute size perspective. Though B of A doesn't have quite the market share of Wells or JPM, a decline in mortgage activity would smart. It would come at an interesting time for the bank, too, as it had retreated from the mortgage market only to more recently look at retrenching as it missed out on the fruits of the refi boom.

Of course we need to keep perspective here. The MBA's report is a weekly one, and one week certainly doesn't make a trend. But, then again, this isn't the first sign we've seen of the mortgage fireworks quieting down.