WATERLOO, Iowa (AP) — The rent for farmland in Iowa has increased 18 percent from last year, reflecting continued strong demand for corn and soybeans. The Iowa State University Extension and Outreach Cash Rental Survey shows the average cash rent for corn and soybean ground in Iowa was $252 an acre per year. Agriculture experts think rates will continue to climb next year despite moves in Congress to end direct commodity payments to farmers. The survey is based on more than 1,400 responses, primarily from farmers, landowners, lenders and professional farm managers. Rents have been climbing for years. In 2008, for example, the statewide rental averaged $176 an acre.