A top financial rating firm downgraded the status of New Mexico’s general obligation bonds, citing large pension obligations and Medicaid costs. A rating downgrade means it will be more expensive for the state to borrow money. General obligation bonds, or GO bonds, are used to finance capital improvement projects, like building state buildings. Moody’s Investors Service announced the downgrade from Aa1 to Aa2 Tuesday. Aa2 is the third-highest rating at Moody’s, below AAA and Aa1, but is still considered an investment grade rating.