Assets of the top 25 banking companies rose 2% during the second quarter, to $2.6 trillion, according to American Banker's latest quarterly survey.
Earnings for the same group of banks, meanwhile, surged 20%, to more than $8 billion.
Although asset trends varied significantly from bank to bank, almost all showed a strong improvement in return on assets, a common measure of profitability.
The relatively insignificant overall rise in assets accompanied by a strong improvement in earnings reflected an increasing trend among banks to securitize assets, getting them off the books, while boosting income from sectors other than lending, said analysts.
"Trading income and equity gains have been strong, and revenues have been growing faster than expenses," noted Ronald I. Mandle, a bank analyst at Sanford C. Bernstein & Co. in New York.
"Capital markets activities have been off the chart," observed Lawrence R. Vitale, an analyst at Bear, Stearns & Co. "There's been a record level of loan syndications and an active securitization market."