Halliburton stock was weak early in the Bush administration, in part because oil prices fell as the world economy weakened in 2001.

He also holds options to buy Halliburton stock.

Over all, the Cheney years saw Halliburton stock underperform most stocks in its industry.

He could, for example, do a "forward sale" of Halliburton stock, delivering it only after the options could be exercised.

That transaction, on May 31, took place just before Halliburton stock began to tumble.

Mr. Cheney sold Halliburton stock, worth more than $20 million, before he became vice president.

Each $1,000 debenture is convertible into 6.824 common shares of Halliburton stock.

The price of Halliburton stock - from thirty-three to sixty-six dollars.

Mr. Cheney sold nearly $40 million in Halliburton stock about the time he left the company at prices above $50 a share.

He had said he would sell his Halliburton stock if the Republican ticket prevailed in the fall.