TAIPEI, Taiwan, June 9(AP) -- Taiwan Semiconductor Manufacturing Co., the world's largest contract chipmaker by revenue, said Friday its sales rose 37.2 percent in May from the same month last year.

The May revenue amounted to 26.77 billion New Taiwan dollars (US$823.31 million; €651.08 million), compared to NT$19.51 billion for May last year, the company said in a statement.

Revenue in the first five months of the year rose 39.5 percent to NT$131.23 billion (US$4.04 billion; €3.19 billion) from NT$94.06 billion in the year-earlier period, the statement said.

The company didn't give a reason for the sales gain.

TSMC's smaller rival, United Microelectronics Corp., Wednesday reported a rise in its May sales of 31.5 percent to NT$8.5 billion (US$263.8 million; €206.16 million) from the same month last year.

UMC reported revenue of NT$41.35 billion (US$1.28 billion; €1 billion) for the January-May period, up 24.9 percent from NT$33.12 billion for the same period last year.

The Taiwanese contract chipmakers supply chips to firms that outsource some of their production to save the cost of constructing chip plants.

The chips are used in a variety of products, including desktop computers, notebooks, mobile phones and digital cameras.