Recreational Equipment Inc. (REI), the nation's largest consumer cooperative, announced a patronage dividend to its members of $11.3 million on 1988 sales of $182.5 million. REI has a mail-order business and a chain of 19 sporting goods stores in the West, including Salt Lake City,

The 10.4 percent patronage dividend is up from the previous year's $9.2 million (10.2 percent) dividend. Although anyone may shop with REI, only members receive patronage dividends, which are based on their annual purchases from the company.Sales for 1988, the company's 50th anniversary year, were up 16.5 percent from $156.7 million to $182.5 million. The company reported pretax profits of $17.7 million, up 36 percent from 1987 profits of $13 million. REI calculates its pretax profits before patronage dividends. Both sales and profit figures include REI's retail and mail order operations, and its manufacturing subsidiaries, THAW Corp. and Mountain Safety Research Inc. (MSR).

After-tax profits increased 65 percent from $3.4 million in 1987 to $5.6 million in 1988.

Based on its 1988 profitability, REI will make environmental and social contributions of $313,752 this year, with major grants going toward the protection of the nation's wilderness, trails and free-flowing rivers. The contributions are up from last year's $250,000.