Ameriprise Financial's ( AMP) profits surged 54% in the fourth quarter. The Minneapolis-based financial services firm, which was spun off from American Express in 2005, made $171 million or 69 cents a share in the fourth quarter compared with $111 million or 44 cents a share a year earlier. Revenue rose 16%, to $2.2 billion. In the fourth quarter, Ameriprise had $80 million, or 33 cents, in after-tax separation costs related to the spin-off. Adjusted profit after taxes rose 30% from a year earlier, to $251 million or $1.02 a share. Analysts were expecting the firm to earn 84 cents a share on $1.88 billion of revenue. Ameriprise said growth "reflected fundamental improvement in asset-based fees, distribution fees and premiums as a result of increasing advisor productivity and market appreciation." The gains were partially offset by declines in net investment income as a result of declining balances in annuity fixed accounts, it says. The company said it was on track to fully separate from American Express later this year. Shares fell $1.41, to $57.45 on Thursday.