Iowans who purchase health insurance through the federal health insurance marketplace will on average see a 12.8 percent increase for the benchmark Silver plan, according to data released Monday by the U.S. Department of Health and Human Services. On average, premiums on the mid-range Silver plans are expected to increase 7.5 percent for the 37 states that use the federal Marketplace that was established under the Affordable Care Act. The projected increases do not take into account advance premium tax credits, which will lower the monthly costs for the majority of Marketplace users to less than $100, the department said. The average advance premium tax credits for those enrollees who qualified for financial assistance was $270 per month. In 2015, 45,612 health insurance plans were purchased in Iowa through the Marketplace.