General Fund spending in New Hampshire has increased by half a billion dollars over the last decade, but the bulk of those increases can be traced to five programs, while most other programs have experienced budget reductions.

Medicaid payments, the retirement system, special education, construction of new schools and the N.H. Department of Corrections accounted for about $422 million in state spending in 2007, up from about $186 million a decade ago, said Stephen Norton, executive director of the N.H. Center for Public Policy Studies.

Norton authored a recent study on changes to state budget priorities over the last decade, taking into account inflation and population growth. Aside from the five major cost drivers, the remaining 80 programs and agencies included in the budget experienced a combined reduction in state services, Norton said.

The five primary cost drivers currently account for about $3.30 of every $10 of taxpayer money going to the state. In 1997, the same five programs represented only $2.10 of every $10, Norton said.

Growth in these programs was necessitated by state laws and federal regulations, so it will be difficult to trim expenses in coming years. Any efforts to do so will have to be preceded by changes in policy and law, the study concluded.