Another huge year for mergers and acquisitions helped Piper Jaffray Companies achieve record annual revenue and significantly beat analysts' earnings expectations for the quarter.

The Minneapolis-based financial services firm reported adjusted net income of $21.1 million, or $1.40 per share, in the fourth quarter and $4.22 a share for the full year. Wall Street analysts, according to Yahoo Finance, were expecting adjusted earnings per share of 87 cents for the quarter and $4.10 for the full year.

"We achieved record revenues and delivered solid results for our shareholders in 2015, while actively investing in the business to position us for continued growth and improved shareholder returns," said Piper's chairman and CEO, Andrew Duff, in a prepared statement.

Piper's record results for 2015 are part of the strategy shift that Duff started after the company emerged from the second wave of the financial crisis in 2011.

Duff said in a conference call Thursday with analysts that his goal was threefold: Increase investment in areas where Piper was most competitive; invest in higher margin, less capital intensive activities such as Asset Management and public finance; and pursue leadership in a diverse range of business.

Four years later, the strategy has paid dividends. "Since embarking on this strategy, we have increased revenue by 50 percent, operating earnings by 150 percent and tripled our ROE [return on equity]," Duff said.

Overall adjusted net revenue for the quarter was $195.1 million, up 31.5 percent from the year-ago period. Net revenue for the year was $663.1 million, up 4.8 percent from 2014. Piper's adjusted results exclude charges related to noncontrolling interests and acquisitions. On a U.S. GAAP basis revenue for the quarter and year were $197.4 million and $672.9 million, respectively.

The year-end results took into account Piper's September acquisition of River Branch Holdings LLC, a Chicago-based investment banking boutique that serves clients in the financial institutions industry, and its October purchase of BMO Capital Markets municipal bond sales, trading and origination business. The bank also is buying Simmons & Company International, a Texas-based investment bank and broker dealer specializing in the energy business that will further diversify Piper's range of business. That deal is expected to close in the first quarter of 2016.

During the year, Piper returned $133 million of capital to shareholders through share repurchases.

Piper's stock closed at $38.08 per share on Thursday, up $5.23 per share, or 15.9 percent on the stronger than expected results.

Patrick Kennedy • 612-673-7926