State Street Corp. shares dropped as much as 11% after the bank reported net interest income and revenue that was weaker than analysts’ estimates.

Net interest income clocked in at $691 million, missing the roughly $700 million average estimate of analysts surveyed by Bloomberg. Lower average non-interest bearing deposits dragged NII down from the previous quarter.

While second-quarter earnings surpassed expectations, the beat was primarily fueled by a lower tax rate and a smaller loan-loss provision rather than business fundamentals.

“We would expect shares to underperform in today’s session” because of the “lower-quality sources of earnings strength,” Wolfe Research analysts led by Steven Chubak wrote in a note.

The trust bank reported a profit of $2.17 per share, higher than the average estimate of $2.10 from 18 analysts in a Bloomberg survey.

Trust banks led the KBW Bank Index’s decliners Friday. State Street’s decline was the most intraday since April. Northern Trust Corp. was lower by as much as 7.4% and Bank of New York Mellon Corp. dropped by as much as 7.6%.

--With assistance from Bre Bradham.