SunTrust Bank's trust and investment management business took another quarterly beating, according to the bank's latest financial results released on Friday.

Second-quarter revenue from trust and investment management services plunged 28% to $84 million from $116 million in the same period a year ago. Revenue was flat from the previous quarter.

For the first six months of 2015, trust and investment services generated $168 million, down 32% year-over-year.

The decline was due to foregone revenue resulting from the sale of asset management firm RidgeWorth Capital Management in the second quarter of 2014, the parent of the Atlanta-based bank said in the earnings release.

At the end of the second quarter, the trust and investment services business had $44 billion in "managed assets" or assets under management, down 13% from $50.3 billion a year ago.

The retail brokerage business, on the other hand, fared much better. Second-quarter revenue from retail investment services climbed 5% to $80 million from $76 million in the second quarter last year. Revenue was also up from the previous quarter, jumping by $8 million, or 11%, from the previous quarter.

For the first six months of 2015, the retail brokerage business hauled in $152 million, 3% more than it brought in last year.  Its assets under management also increased, climbing 5% to $48.5 billion from $46.2 billion a year ago. 

Overall, SunTrust Banks, the parent of SunTrust Bank, earned $467 million in the second quarter, or 89 cents per average common diluted share, compared with $387 million, or 72 cents per share, it earned in the same quarter a year ago.

"Our performance this quarter demonstrates solid execution of our key strategies¬ódeepening client relationships, optimizing the balance sheet, and improving efficiency. This was evidenced by higher revenue, continued deposit growth and improved returns," William H. Rogers, Jr., chairman and CEO of SunTrust Banks, said in a statement.

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