Iowa workers’ compensation premiums would increase an average of 2.2 percent in 2016 under a proposed increase filed last week with the Iowa Insurance Division. The filing proposes an overall average increase of 2.7 percent in both voluntary rates and in assigned risk rates. Proposed adjustments in two factors bring the overall average premium increase to 2.2 percent. By comparison, the 2015 rate was reduced by 3.7 percent for both the voluntary rates and assigned risk rates. Claim frequency flattened out in policy year 2013, according to the National Council on Compensation Insurance Inc., which conducted the analysis. However, despite slightly reducing projections for medical costs, a rate increase is still needed based on the most recent medical loss ratios, the organization said.