You can view their stats here. But they don’t separate out OOS, and they haven’t updated for 2023.
The overall admit rate for Fall 2022 was 34.3%. At state schools, OOS admit rates are typically lower than the average - and since only about 23% of UMD students are OOS but make up more than 55% of applications, “upper 20s” would be a good guess for fall 2022, OOS admit rate. Expect it to drop lower for 2023 and 2024.
Of course, admission rates for certain majors are significantly below this university-wide average. Public policy is one of them, as UMD is highly ranked for this major.
Similarly with stats, as an OOS student, expect them to be higher than the averages published here.