American Stores Co. announced net earnings for the 1989 53-week fiscal year of $118.12 million, or $3.45 per common share, a 20.2 percent increase compared with $98.25 million, or $2.54 per common share, in the same period of 1988.

Fourth-quarter net earnings increased to $53.12 million, or $1.61 per common share in 1989 compared with $20.23 million, or $.52 per common share in 1988. The company said results of its acquisition of Lucky Stores Inc., based in California, are included from June 2, 1988.Sales for the 1989 fiscal year amounted to $22.00 billion, an increase of 19.1 percent over the prior year. Sales increased 14.0 percent to $6.14 billion for the 1989 14-week fourth quarter when compared with the 1988 13-week fourth quarter.

Operating profits increased 35.8 percent to $603.52 million for the year ended Feb. 3, 1990, compared with $444.33 million reported in the prior year. The 1989 fourth-quarter operating profits increased 45.4 percent to $196.71 million compared with $135.27 million in the 1988 fourth quarter.

Operating profits for all of the company's major subsidiaries exceeded amounts reported in the 1988 fiscal year for both the year-to-date and the fourth quarter. Lucky Stores and American Food and Drug reported the strongest annual improvements in operating profits.

For the 53 weeks year-to-date, preferred dividends amounted to $8.60 million in 1989 compared with $21.43 million in 1988. No preferred dividends were paid in the fourth quarter of 1989 compared with $4.29 million in the fourth quarter of 1988.

During the third quarter of 1989, the company converted 3,809,000 shares of Series A Preferred Stock into 4,105,000 shares of common stock. The effect of the conversion of Series A Preferred Stock into common stock increased earnings per common share by $.11.

In addition to the Series A conversion, the lower preferred dividends in 1989 reflect the company's redemption of its Preferred B Stock on Aug. 15, 1988. Average common shares outstanding for the year were 31,713,000 in 1989 and 30,185,000 in 1988. As of Feb. 3, 1990, there were 34,471,000 shares of common stock outstanding.

American Stores Co.'s principal grocery and combination store operating subsidiaries include American Superstores Inc. and its subsidiaries Acme Markets Inc., Jewel Foods Stores and Star Market Co.; American Food and Drug Inc., and its divisions, Skaggs Alpha Beta and Buttrey Food Stores; Jewel Osco; Lucky Stores Inc., and Alpha Beta Co. American Stores Co.'s drug subsidiary is American Drug Stores Inc., which operates under the Osco Drug and Sav-on names. The company operated 1,894 retail food, drug and combination food/drug stores (including 141 Jewel and Osco combination stores) in 40 states as of Feb. 3.