The Carlyle Group saw fourth-quarter net income drop 28 percent compared with a year ago as the value of its portfolio companies slowed toward the end of 2012.

Economic net income, one key metric, dropped to $182 million in the final quarter compared with $254 million in the final quarter of 2011, according to the company’s fourth-quarter earnings report, which it released Thursday.

The company recorded unrealized losses on real estate in the fourth quarter, which contributed to its drop in economic net income.

Carlyle’s shares, which have soared more than 50 percent since it went public last May, were down slightly in early trading Thursday.

Carlyle continues to be a fundraising machine and one of the busiest dealmakers in private equity. The company reported $170 billion under management, up from $157 billion at the end of the third quarter.

It raised $14 billion in new capital in 2012, double the amount it raised in 2011, in a sign that its limited partners — the institutions and wealthy individuals who give the firm its money to buy and sell companies — have confidence in the firm’s ability to produce returns.

As for deals, Carlyle invested $3.3 billion in 96 investments during the fourth quarter, including four major U.S. buyouts of Hamilton Sundstrand Industrial, Landmark Aviation, Getty Images and Genesee & Wyoming railroad.

Carlyle also invested in an agricultural trading firm in sub-Saharan Africa, its first in that part of the world. The firm committed to several investments that are closing this quarter, including DuPont Performance Coatings, TCW and Duff & Phelps.

“I am optimistic about investment opportunities globally, in developed and emerging markets alike,” said Carlyle co-chief executive William E. Conway Jr., in a news release.

Carlyle was in talks to purchase the Nasdaq stock exchange, but those talks did not advance beyond early stages.

The shareholders, those who hold Carlyle stock on the open market, will receive an 85- cent quarterly dividend, which reflects the health of the firm in its first year as a public company.

“We had another excellent year,” said co-chief executive David M. Rubenstein. “Our performance over the past two years was marked by steady, continuous progress across our business.”