UPDATE 1-Mexico retailers April same-store sales fall

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MEXICO CITY, May 13 (Reuters) - Mexican retailers group ANTAD said on Tuesday its members' same-store sales fell 3.4 percent in April compared with the same month a year ago.

ANTAD, which counts supermarket giants Wal-Mart de Mexico (WALMEXV.MX) and Soriana (SORIANAB.MX) among its members, cited and early Easter and one Sunday less last month as reasons for the decline.

Same-store sales -- which measure performance at stores that have been open for at least 12 months -- fell 1.3 percent in April of last year.

Easter, when many Mexican families take long holidays and make purchases for trips, was in March this year, compared with early April in 2007.

Regardless of the calendar effect, sales of Mexican retailers have suffered in recent months due to slowing consumption and more cautious purchases from customers amid a tough economic environment. (Reporting by Cyntia Barrera Diaz)