FBL Financial Group Inc. reported double-digit increases in first-quarter operating income and net income, with results buoyed by strong life insurance sales and higher investment income. Net income for the quarter was $25 million, or 96 cents per share, an 81 percent increase from the $16.6 million and 53 cents per share reported in the year-ago period. Operating income, which excludes investment gains and losses, totaled $23.1 million, up 39 percent from the first quarter of 2012. Life insurance premiums collected increased 27 percent, while annuity premiums collected declined 28 percent, reflecting the focus on life insurance sales and the suspension of certain annuity products due to the low interest rate environment, the company said in an earnings release.