State Street Corp. said Wednesday that fourth-quarter earnings rose sharply from year-ago levels, but clients took less risk, hurting key fees for the Boston-based custody bank.

Net income available to common shareholders was $371 million, or 76 cents a share, compared with $81 million, or 16 cents a share, in the year-ago period. Year-ago results included charges for restructuring and repositioning an asset portfolio.

Fourth-quarter results included a pre-tax charge of $120 million, or 15 cents a share, mostly related to State Street’s withdrawal from its fixed-income trading initiative.

State Street said fourth-quarter revenue rose 13 percent to $2.32 billion from the year-ago period. But it dropped 5 percent from the third quarter as shaky global markets sidelined some clients adverse to risk.

Servicing fees, for example, dropped 1 percent to $1.06 billion from the year-ago period, reflecting less risk-taking by clients, State Street said in a press release.

Investment management fees and trading service revenue, declined 9 percent and 12 percent, respectively. Combined, those two categories generated $475 million in revenue in the fourth quarter.

Overall, total operating revenue in the fourth quarter rose 0.2 percent to $2.29 billion from the year-earlier period.

Meanwhile, the company said it expects to record an aggregate, pretax conduit-related gain of about $1.1 billion in interest revenue beginning this year through the remaining terms of the securities. The expectation is based on numerous assumptions, including holding the securities to maturity, the company said.

On the expense front, State Street said compensation and employee benefit costs were $872 million in the fourth quarter, down 10 percent from the previous three months.