U.S. wholesale inventories increased by more than expected in April even as wholesale sales increased, according to figures released Friday by the Commerce Department. Total inventories of merchant wholesalers were recorded at a seasonally adjusted level of $483.5 billion at the end of April, a 0.6 percent increase from revised March levels, which were also up slightly from initial reports. Economists had expected wholesale inventories to increase by about 0.5 percent. On a year-over-year basis, U.S. wholesale inventories were up 8.2 percent from April 2011 levels. April also saw an increase in sales at the wholesale level, with the Commerce Department figures showing a 1.1 percent increase to a seasonally adjusted level of $415 billion, up 6.8 percent from April 2011 levels. Despite the larger increase in sales than in inventories, the inventories-to-sales ratio held steady at 1.17 in April. The increase in wholesale inventories was driven by a 1.1 percent increase in inventories durable goods, which more than offset a 0.1 percent decline in inventories of non-durable goods. The April increase in durable goods inventories is the strongest since May 2011. Automotive wholesalers recorded a 1.7 percent increase in inventories, while professional equipment inventories rose 1.4 percent, paper inventories jumped 3.9 percent, machinery inventories climbed 2.4 percent and petroleum inventories advanced 2 percent.