The Michigan Senate Fiscal Agency estimates the state brought in more tax revenue in 2011 than was originally predicted, and the revenues reveal an unusual situation, state sales tax revenues grew faster than income.
"In many cases there were places where revenues were growing faster than income, which isn't something that generally is sustainable," says David Zin, an economist with the agency.
The agency is preparing its economic forecast for a conference later this month that will come up with revenue estimates used to balance the state budget.
Zin predicts the state's economy will grow slowly over the next couple years and pick up in 2014, but he says economists have varying opinions on whether the state and the nation will dip into another recession.
The House and the state Treasury are also putting together separate forecasts.