Some of the programs that are authorized in a farm bill fall into the spending category of mandatory, while others are discretionary. Programs with mandatory funding have their funds authorized directly within the farm bill. On the other hand, programs with discretionary funding require for congressional appropriators to designate funding to them because they are not funded directly in the farm bill. Cost projections for funding estimates are calculated by the Congressional Budget Office using a baseline, which is an estimate of future costs over 10 years if the existing costs were to continue unchanged. Adjustments to funding levels between programs generally occurs from one year to the next, incrementally.