A new survey of Illinois school districts shows most are continuing to have trouble filling open teaching positions with qualified teachers and even more are having difficulty hiring substitute teachers.

It’s a problem that has existed in the state for many years and one that experts attribute to a variety of factors, such as low pay and the difficulty in attracting new teachers to work in certain parts of the state.

The survey has been conducted each of the past four years by the Illinois Association of Regional Superintendents of Schools. Regional superintendents are in charge of supervising schools in the state’s 38 educational regions and operating regional offices of education. They also act as a kind of conduit of information and support between the Illinois State Board of Education and the state’s 853 local school districts.