Kia Motors America reported its best-ever monthly sales in May, selling 48,212 units, a 53.4% increase from May of 2010 and a 2.4% increase from April, the previous record setting month.Year-to-date, Kia America’s sales are up 44.8% over the first five months of 2010, and the company's share of the U.S. market hit an all-time high.Byung Mo Ahn, group president and CEO of KMA and Kia Motors Manufacturing Georgia (KMMG) said, "Kia's record performance this year, and in the last three months, is a testament to our comprehensive and fuel-efficient vehicle lineup, which offers world-class styling and cutting-edge technology to today's discerning shoppers. Consumers are increasingly focused on fuel economy, and with Optima Hybrid arriving in showrooms this month and the debut of the 2012 Rio and Rio5 sub-compacts this fall, Kia will offer three vehicles that achieve 40 miles per gallon before the end of the year."The increasingly popular urban passenger vehicle, the Kia Soul, continued its blistering sales growth, up 81% year-over-year to 11,157 units in the month. Year-to-date sales now total 43,673, an increase of 97% over the first five months of 2010.Sales of the Optima grew a blistering 210% year-over-year to 7,431 units, sales of the Sportage grew 98% to 4,550, and sales of the 2011 Sorento grew 46% to 11,936.