Suppose Caterpillar, Inc., has 675 million shares outstanding with a share price of $74.59, and $25.89 billion in debt. If in three years, Caterpillar has 695 million shares outstanding trading for $85.94 per share, how much debt will Caterpillar have if it maintains a constant debt-equity ratio? The amount of debt required in three years will be $billion. (Round to two decimal places.)