Yum! Brands Inc., which gets more than 50 percent of its revenue from China, said same-store sales in the Asian nation last month fell more slowly than in April as cases of avian flu subsided.

Sales at stores open at least a year dropped 19 percent in May, the Louisville, Kentucky-based company said in a filing with the U.S. Securities and Exchange Commission Tuesday. That followed a 29 percent decline in April and matched analysts' estimates for a 19 percent decline, the average of eight projections compiled by Consensus Metrix.

Chief Executive Officer David Novak has been trying to reassure Chinese consumers that the company’s chicken is safe to eat after a deadly outbreak of bird flu and a former supplier was probed for selling chicken with too much antibiotics. The 25 percent drop for KFC stores is an improvement from April’s decline of 36 percent.

Yum, which has more than 5,400 KFC and Pizza Hut stores in China, fell 0.4 percent to $71.50 at 4:34 p.m. in New York. The shares gained 8.1 percent through the close of regular trading Tuesday, while the Standard & Poor’s 500 Index advanced 14 percent.