Ambac Financial Group is the latest company to sacrifice its common stockholders to defend its credit rating in the wake of the sub-prime mortgage crisis.

The second-largest bond insurer Tuesday announced that it will slash its dividend by two-thirds, to seven cents per share, as part of a wider plan to boost cash. It also said it would issue at least $1 billion of equity and equity-linked securities in a determined bid to maintain its triple-A financial strength.

“By raising at least $1 billion in capital, Ambac is expected to meet or exceed Fitch Ratings’ current triple-A capital requirements for the company,” the company said in a statement. It added that its existing capital position currently meets or exceeds the triple-A capital requirements of both S&P and Moody’s.

On Monday, Citigroup stunned some investors when it said it would cut its dividend by 41 percent.

“Given the fact that the company is going to wind up with perhaps some excess capital, I find it difficult to understand why you would cut the dividend,” Dick Bove, an analyst at Punk Ziegel, said during the Citi conference call on Tuesday, according to marketwatch.com. “By cutting the dividend, you have knocked at least $5 billion off the value of the stock. I’m wondering where the shareholder shows up in this whole calculation?”

Last week, MBIA Inc., the largest bond insurer, said it will cut its dividend 62 percent and raise $1 billion in a sale of notes, also in an effort to preserve its triple-A credit rating.