Profits at Securian Financial Group rose 7 percent last year to $226 million, largely driven by sizzling growth in the company's asset management business.

The St. Paul company also enjoyed a big surge in sales of variable annuities, a retirement product many companies exited in recent years.

Securian, one of the state's largest privately held companies, provides a range of insurance and financial services for individuals and businesses. It's perhaps best known as the parent of Minnesota Life Insurance Co. and Advantus Capital Management, which manages investment portfolios for insurance companies, pension plans, foundations, endowments and mutual funds.

Total sales at Securian grew 37 percent to $3.9 billion. Total assets under management rose 15 percent to $42.1 billion.

Much of the growth was driven by a 93 percent increase in sales at Advantus, now Securian's largest business unit by sales. Sales at Advantus hit $1.6 billion.

In an interview, Bob Senkler, Securian's longtime chairman and CEO, attributed the big expansion at Advantus to its success selling its asset management services to other insurance companies.

Chris Sebald, president and chief investment officer for Advantus, said most of the growth came from scoring a block of business from a U.S. life insurance company that it cannot name. Sebald called it a "big win."

"We were competing against many of the largest asset managers in the industry," Sebald said.

Securian's other business units also fared well.

Sales of annuities, mostly variable annuities, soared 57 percent to $936 million.

Senkler said that the risk profile of variable annuities has turned around from six years ago and the company is benefiting from that as baby boomers eye retirement.

"It's a major product that people will continue to value," Senkler said. "We find the market very attractive."

Senkler said he sees the trend continuing for the next two or three years.

Annuities are insurance products often used for retirement that pay buyers a regular stream of income. Unlike fixed annuities that offer a guaranteed payout, variable annuities offer a stream of payments based on the performance of underlying investments, and generally carry higher risk.