Concord — Ignoring demographic trends is like driving down a dark road without headlights, a state lawmaker said on Wednesday in supporting a bill to make policymakers better planners.

The state’s population is expected to undergo a dramatic shift over the next two decades, when the number of residents age 65 and older is projected to double. Rep. Neal Kurk, a Republican from Weare, N.H., is co-sponsoring a bill he said would help lawmakers prepare for that change by breaking out of their two-year budget cycle mentality.

“We need to understand how that population bulge is working through and what it means for us,” Kurk told the House Executive Departments and Administration Committee.

While lawmakers currently get some short-term, statewide population projections, they are of limited use because demographic changes affect the less-populated North Country far differently than the densely-populated southern region, he said.

“We recognize this and we make efforts that are not fully informed. We need better information,” he said. “Let’s not go into the future blindly, and let’s say the future is longer than the two year budget projections.”

The bill, which incorporates recommendations of a study committee appointed last year, would create a state demographer position and a commission to develop long-term migration goals and recommend legislation.

It also would require several state agencies to make 10-year budget projections that reflect demographic changes and would provide lawmakers with information about how proposed legislation would affect demographics.