Those unobligated reserves include $61.4 million in revenue collections above the amount appropriated by the Legislature and $32 million "in savings at the Division of Medicaid."
It has been previously reported that, based on preliminary figures, the state exceeded the revenue collections estimate that was used to build the budget by $62 million.
State law dictates a portion of the surplus be directed to the state general fund for appropriation by the 2012 Legislature and smaller portions be placed in the state rainy day and capital improvements funds.
For the fiscal year, which ended June 30, actual collections were $4.58 billion, or 2.85 percent above the amount collected the prior year, according to the Joint Legislative Budget Committee.
In recent years, the Legislature and Barbour have had to make budget cuts because of an unprecedented drop in state tax collections. The 2.85 percent growth in tax collections for the recently completed year comes after two years in which the state collected less revenue than it did the previous year for the first time in recent memory.
"Through conservative management, we have steered the state through the worst national economy in generations," Barbour wrote to legislators.
But the outgoing governor cautioned about future budgeting efforts.
"Mississippi, like many states, still faces a slow, inconsistent recovery from the national recession," he added. "Our state budget will not fully recover until Fiscal Year 2014 or later."
He said the state revenue collections still were 7 percent below the peak that occurred four years ago.
State revenue comes from a variety of sources, but the bulk of it is from taxes on retail items and income.
For the year, corporate taxes were 14 percent, or $54.9 million, above the estimate while sales taxes were $25.8 million, or 1.5 percent, above the estimate and individual income taxes were $29.7 million, or 2.2 percent, above the estimate.
For the month of June, the state collected $23 million above the estimate - despite a drop of $2.7 million in casino gambling taxes caused primarily by the Mississippi River flooding.