* Sport: Redshirting is far more common in some sports (football, basketball) than others. In sports with smaller rosters and less substitution, redshirting is less prevalent.
* Division: Division I schools might have more redshirted athletes compared to Division II or III due to higher scholarship limits and greater competition for roster spots.
* Individual Team Circumstances: A team with many talented upperclassmen might redshirt more freshmen. A team with significant injuries or departures might not redshirt anyone.
While some research papers and articles might touch upon redshirting rates within specific sports or divisions, a universal percentage is not tracked or easily calculated. You'd likely have to conduct a very large and detailed study across many schools and sports to even attempt to estimate a broad percentage.