The number of outbound tourists leaving China reached 37.92 million in the first five months this year, up 17.3 percent compared with the same period in 2012. However, the number of overnight inbound tourists dropped - Inbound overnight visitors reached 22.93 million between January and May, down 4.06 percent over the same period last year. China has the world's largest domestic tourism market and outbound Chinese tourists are the biggest spenders worldwide.