AUSTIN, Texas (AP) - An expert economist has testified in the public school finance trial that Texas teacher quality in the state is dropping, largely because of low pay in a competitive market.

Duke University Professor Jacob Vigdor said Tuesday that teacher salaries in Texas are 30 percent lower than for other college graduates and has fallen behind those paid in neighboring states.

Vigdor said 32 other states pay higher salaries, which in Texas have not kept up with inflation since 2000.

He said state data schools have added 270,000 more students, but have 3,400 fewer teachers. He cited statistics from 2010.

Vigdor added that student achievement will likely drop as a result of lower quality teachers.

More than 600 school districts have sued the state over $5.4 billion in cuts to school funding.