What happened?
JPMorgan Chase (NYSE:JPM) basically inaugurated earnings season for the nation's major incumbent banking groups, reporting its Q4 and fiscal 2015. For the quarter, net revenue saw an incremental rise to $23.7 billion, while net profit zoomed ahead by 10% on a year-over-year basis, to $5.4 billion ($1.32). Both figures topped analyst expectations.

For the year, JPMorgan Chase posted revenue of $96.6 billion, and a bottom line of more than $24.4 billion, the latter a new annual record for the company. Fiscal 2014's $21.8 billion was the previous all-time high; that year, the company's top-line came in at $97.9 billion.  

Does it matter?
JPMorgan Chase delivered good performance for both periods, growing its profitability in a period that has been challenging for banks. After all, for most of the year, interest rates were stuck stubbornly at near-zero levels.

It achieved this growth mainly through a reduction in expenses. Most notably, these included a steep drop-off in legal costs. Like fellow big financials such as Bank of America, Citigroup, and Wells Fargo, JPMorgan Chase had to contend with a raft of costly lawsuits and settlements related to its conduct during last decade's financial crisis. This period seems to be coming to an end.

The cost savings more than offset the declines the bank reported in some of its key business areas. Investment banking revenue declined by 11% during the quarter, to below $1.5 billion, due largely to a steep fall in debt-issuance revenue. On the other hand, divisions such as consumer and community banking, and card, commerce solutions and auto, saw increases in their top lines.

Although it would be more encouraging if JPMorgan Chase improved its results more organically, through broad revenue growth, the advances in profitability show the bank is in more than decent shape. This, combined with Citigroup's strong Q4 and 2015 showing, indicate that big banks as a group are not doing badly at all (although Wells Fargo's performance was basically flat). We'll get a more complete picture once fellow incumbent Bank of America releases its results.

Bank of America is scheduled to do so on Tuesday. Wells Fargo and Citigroup both reported earlier on Friday.