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MEXICO CITY, May 29 (Reuters) - Mexico's peso strengthened on Friday after data in the United States and Japan fueled hopes the worst of the global economic downturn is over, although stocks ended lower.

The peso MXN= MEX01 strengthened 0.57 percent to 13.1750 per dollar.

Revised first-quarter U.S. GDP figures showed less of a contraction than initial estimates, while another report showed Japanese factory output jumped in April at its fastest rate in more than a half century.

The data boosted "further speculation that the worst of the global recession may be over," RBC Capital Markets said in a note to clients.

Mexico sends about 80 percent of its exports to the United States.

The IPC stock index .MXX fell 0.1.33 percent to finish at 24,331.17 points after spending much of the day in positive territory.

Cellphone operator America Movil (AMXL.MX: Quote, Profile, Research), controlled by billionaire Carlos Slim, slipped 3.1 percent to 24.98 pesos.

For the week, the IPC index rose 1 percent and the peso was about flat.