Hawaii’s general-obligation bonds had their rating cut to Aa2 from Aa1 by Moody’s Investors Service, affecting about $5.1 billion in outstanding debt.

The downgrade to the third-highest ranking reflects Hawaii’s “strained financial operations following the recession-driven fall-off over the last several years,” Moody’s analysts Nicole Johnson and Nicholas Samuels said in a report today.

The latest projections for fiscal 2011 revenue is 1.6 percent lower than last year and 8 percent below the recent peak in 2008, the analysts said, reflecting in part the natural disasters in Japan that reduced tourism from that country.

The state faced a $539 million deficit for its 2012 fiscal year and $498 million for 2013, amounting to 10 percent and 8.6 percent of operating revenue.

The biennial budget was balanced with $652 million in revenue enhancements, such as the suspension of excise-tax exemptions and an increase in surcharges on car rentals.

Expenditure reductions totaling $777 million over two years included cuts in Medicaid services and public welfare. The state’s largest workers’ union agreed to a 5 percent pay reduction and increased health-care contributions.

The state’s reserves, as high as 20 percent of revenue following the 2001 recession, show a negative balance for 2010, the Moody’s statement said.