The Texas Comptroller - as required by the Texas Constitution - is expected to provide the biennial revenue estimate for 2014-2015. This will guide the members of the 83rd Session of the legislature as they put the state budget together. Expenditures cannot exceed the estimate, but the estimate is guaranteed to be off at leas some since its tough to project what the economy will be like in 2014 and 2015, which means that we will not know what tax revenues will be.
The Dallas Morning News points out that the previous estimate underestimated revenue by perhaps $12 billion.