Fourth-quarter results at Bank of America (BAC -0.13%) confirm the trend started yesterday by JPMorgan Chase, where revenue and net income was materially affected by lower mortgage banking and trading activity.

For the three months ended Dec. 31, Bank of America earned $3.1 billion compared to $3.4 billion in the same period last year. Its revenue, net of interest expense, came in at $19 billion, down from $21.7 billion in the year-ago period.

That this wasn't a surprise, as all of the banks had prepared investors for lower results, hasn't calmed the market. Roughly an hour into Thursday's trading session, Bank of America's shares are trading down by nearly 3%.

Far and away the biggest drag on the North Carolina-based bank's fourth-quarter results came from its global markets segment, which primarily reflects its trading operations. Excluding noncash charges stemming from the valuation of Bank of America's own debt, revenue in the unit fell by 21.5%, only slightly better than the 23% drop experienced by JPMorgan's analogous unit.

The dramatic decrease in oil prices over the latter half of 2014 has convulsed currency, commodity, and fixed income markets. While some volatility is good, too much of it suppresses client activity and can negatively impact a bank's own asset portfolio, which is precisely what happened at Bank of America.

 In addition to disappointing trading profits, lower mortgage banking income weighed heavily on a year-over-year comparison of Bank of America's top and bottom lines. Net revenue in its consumer real estate services segment fell by $538 million, or 31.4%, from the fourth quarter of last year.

The drop, however, wasn't due to lower origination activity, as it underwrote $15 billion worth of first-lien residential mortgages and home equity lines of credit. It was due instead to a drop off in the size of Bank of America's mortgage servicing portfolio, which the bank has been strategically reducing since its fateful acquisition of Countrywide Financial on the eve of the financial crisis.

The top and bottom line numbers aside, it wasn't a universally disappointing quarter for the nation's third largest bank by assets. Again, continuing the tone set yesterday by JPMorgan and Wells Fargo, Bank of America turned in a solid performance for its bread-and-butter consumer banking franchise, with both deposit balances and credit card issuance up by healthy margins.

Moreover, the bank's wealth management division saw a nearly 3% yearly increase in net revenue, though higher expenses weighed on the unit's profitability.

All in all, for current or prospective investors in Bank of America, it was simply another quarter of mixed results from a bank that's still paying for the strategic mistakes of its former management. If anything, in turn, the recent correction in price should be a welcome development for Bank of America bulls that believe it will one day return to the ranks of the nation's elite lenders.