Shares of Goldman Sachs Group Inc. (NYSE:GS) dropped more than 1 percent Friday after the investment bank’s division that trades bonds, currencies and commodities, traditionally one of the company’s strongest divisions, saw its profit plunge 29 percent last quarter. The bank's bond trading division struggled following multiple bouts of volatility last quarter, driven by multiple factors, including dropping oil prices and uncertainty about global economic growth.

Although the firm topped overall Wall Street forecasts for quarterly earnings and revenue, the New York-based company’s weaker-than-expected results in its fixed-income division closed out a week of lackluster results from the U.S. banking sector, as rival JPMorgan Chase & Co. disappointed investors on Wednesday, followed by weaker-than-expected results from Citigroup Inc. and Bank of America Corporation on Thursday.

Overall profit at Goldman Sachs dropped 7 percent last quarter compared with a year ago, but still beat analysts’ expectations.

Goldman Sachs reported fiscal fourth-quarter net income of $2.17 billion, or earnings per share of $4.38, on revenue of $7.69 billion, compared with a profit of $2.25 billion, or earnings per share of $4.60, on revenue of $8.78 billion a year ago. Wall Street had forecast Goldman Sachs to report net income of $2.24 billion, or earnings per share of $4.68, on revenue of $7.9 billion, according to analysts polled by Thomson Reuters.

Net revenue in the bank’s division that trades bonds (or fixed income, currencies and commodities) tumbled 29 percent, to $1.22 billion, in the fourth quarter of 2014. Meanwhile, investment banking revenue dropped 16 percent, to $1.44 billion, last quarter compared with a year earlier, and 2 percent lower than the third quarter of 2014.

“During 2014, fixed income, currency and commodities client execution [Goldman Sachs’ division that trades bonds, currencies and commodities] continued to operate in a challenging environment as economic uncertainty contributed to generally low levels of activity, particularly in credit products, interest rate products and mortgages,” Goldman Sachs said in a statement Friday.

The investment bank earned stronger-than-expected profits during the third quarter, but investors expressed concerns over sustainable returns.

For the full year, Goldman Sachs reported net earnings of $8.48 billion, or earnings per share of $17.07, on net revenue of $34.53 billion.

Following the report, shares of Goldman Sachs dropped 1.67 percent, to $175.51, on the New York Stock Exchange.