The list of major companies announcing mass layoffs grew on Monday as Pfizer, Home Depot, Caterpillar, Sprint Nextel and at least eight other firms announced plans to cut more than 75,000 jobs. Pfizer said it would cut nearly 20,000 jobs as part of its acquisition of Wyeth. Caterpillar plans to eliminate 20,000 as well. 8,000 jobs are being cut at Sprint Nextel, 7,000 jobs at Home Depot, 3,400 jobs at Texas Instruments and 2,000 jobs at General Motors. Last week, Microsoft announced it would cut as many as 5,000 jobs in the company’s first mass layoffs.