I'm calling medium sized schools like forest city and charles city, their marching band sizes are a shell of themselves. Go to algona band festival or the mason city band fetival and you see few bands now and the ones you do are the size of a small pep band.
I think the trend in smaller schools is the entire music department is dying.
When I was in school I would guess at least 75% of kids were involved in at least one part of the music department, if not more. When my oldest went through it was probably less than only 25%, now its even less.
In many small schools, eliminating the entire music department would barely be noticed.
You look at a school with 100-150 kids in the high school you will often see less than 20 kids in band, and similarly in Choir, many times the same kids in both (although many small schools are making that hard because of the scheduling and class requirements.
When you look at the large schools 4A-5A having 200+/- in band it really is still less than 20% of the student population. As most if not all of those schools have well over 1000 kids in high school. (smallest 4A has about 600, largest 5As have 2000 plus) The Ankeny schools mentioned have about 2000 students, so a 200 person band is only about 10% participation.
If you go with a 10% participation rate that really shows how schools at the 1A level and below, have tiny bands, that are barely hanging on.
When I was in school my school had about 180 in high school. The band averaged in the 50-75 range, choir was around 100. Last I knew, the same school now is about 120, and the band at times is in the single digits, same with choir, but usually below 20 each, they add in the middle school kids to get enough to actually be functional. I think the average is about 5 kids in band per class, I believe similar or less for chorus. Although I dont live there anymore so only going on knowledge from social media posts they put out etc.