The Macquarie group had its second credit downgrade in four days. The first was by Fitch on Tuesday and the second by Moody's Investors Service on Friday. Moody's cut Macquarie's credit rating by one notch to A3 from A2.

At the same time, the rating agency also reduced the senior unsecured debt rating of Macquarie to A2 from A1. The unsecured debts provide funds for the majority of the group's activities. The downgrade is part of Moody's review of Macquarie's ratings since November 2011 and the agency's broad review of banks and securities firms on the global markets.

"Today's rating actions reflect ongoing earning challenges for Macquarie and the evolution of its business model against the backdrop of protracted weakness in financial markets," Macquarie Senior Vice President Patrick Winsbury said in a statement.

Macquarie said that it has made vital adjustments to its business but the firm's sustainability and profitability are hard to predict due to the ongoing initiatives.

Fitch downgraded Macquarie's long-term issued default rating to A- from A and its long-term issuer default rating to A from A+ on Tuesday. With the similar action by Moody's on Friday, all three rating agencies including Standard and Poor's have cut Macquarie's ratings.

"Following the conclusion of these extensive industry reviews by the three major credit ratings agencies, Macquarie Bank's strong capital, funding and liquidity positions, together with its risk management track record has been recognised by it being rate A across the board," Macquarie Chief Financial Officer Patrick Upfold said.

On the same day, Moody's also placed Pitney Bowes's investment-grade rating on review for a possible downgrade due to continuous deterioration of the mail and document services firm's operating results. In February, Fitch cut the U.S.-based Pitney Bowes rating for the second time in six months due to the firm's accelerating revenue declines caused by shifting consumer preference to email and other modern means of communication over the traditional mail.