It sells 19% of all grocery-store food in the United States, making it the largest food seller. It plans to double grocery and related sales from $82 billion to $165 billion during the next five years, which would give it command of 35% of the market. It plans to open 40 supercenters in California over the next five years, which is a major cause for the grocery strike in southern California. Managements at the three major grocery stores in southern California, where 70,000 United Food and Commercial Workers (UCFW) workers are striking, have said they are trying to renegotiate lower employer contributions to health-care benefits, because they fear that Wal-Mart plans to saturate southern California with stores, and they will be unable to compete.