Debt-to-Equity Ratios The total debt and stockholders' equity for three companies follows. The companies are described as follows:

AT&T provides long-distance phone service and is a large, well-established company. Micron Technology is a fast-growing producer of memory products for electronic systems. Amgen is a biotechnology company pioneering the development of products based on advances in recombinant DNA. Total Debt Stockholders' Equity (in millions) 2002 1992 2002 1992 AT&T $42,960 $17,122 $12,312 $20,313 Micron Technology 1,189 213 6,306 511 Amgen 6,170 440 18,286 934 1. Compute debt-to-equity ratios for each company for 1992 and 2002. 2. Discuss the differences in the ratios across firms. 3. Discuss the changes in individual company ratios from 1992 to 2002.