MUNSTER, Ind. (AP) — Education experts say Indiana's lingering teacher shortage is being driven in part by a drop in teacher's pay even as educators are being asked to do more in the classroom.

The U.S. Department of Education said that in Indiana, inflation-adjusted teacher pay has fallen since the 1999-2000 school year to the point where teachers now earn almost 16 percent less than they did two decades ago.

"While every teacher understands the demands of the profession, those demands have increased over the years without compensation or respect for the profession," Munster Teachers Association President Ryan Ridgley told The (Northwest Indiana) Times .

Ridgley said the reasons people aren't going into education vary and include Indiana linking students' standardized test scores to teacher evaluations and the fact that teachers may not see sustained pay increases as the cost of living increases.

According to 2015 data from the Indiana Commission for Higher Education, enrollment in teaching programs and those graduating with teaching degrees declined 37 percent from 2004 through 2014. A survey of the past three years by Indiana State University professor Terry McDaniel confirms superintendents statewide are experiencing more difficulty finding teachers.

"As a department, we will continue to pursue any available funding from our legislators to assist districts in boosting teacher pay," Indiana Department of Education spokesman Adam Baker said. "Working to attract and retain excellent teachers is a commitment of this department."