As quoted in Sen. Mary Lazich: Legislature Should Give Schools the Tools to Keep Them Safe. (News release, 11/23/2015)
So, Mary, when is data not data.
From a layman's perspective, it appears that the many other states have more significant reporting problems.
From the National Center for Education Statistics
The symbol ! is a warning to interpret data with caution.
The other symbol, which I can't replicate, indicates that reporting standards not met.
Neither of these appear with Wisconsin's latest data.