IBM says its board had added $5 billion to its stock buyback program, bringing the total buyback authorization to $11.7 billion.

The computer and consulting company last added to it buyback program in April, in the amount of $7 billion. IBM Corp. said Tuesday that it expects to add more funding to the buyback program next April.

The total buyback authorization is equivalent to 5 percent of the Armonk, N.Y., company's outstanding shares.

Buying back shares increases the value of shareholders' existing stakes and can help support a company's per-share earnings