Football Outsiders do a great statistic called Adjusted Games Lost. The 2016 Bears hold the all time record by their calculations with 158.8 AGLs, which simplified massively might be the equivalent of 10 starters missing the entire season. The article explains how they weight for the impact of the player (I.e., importance of position, starter vs. reserve, etc.).
Long article but worth a read, and maybe a check back later in the season to see how your team fared as they also compare to actual performance which makes for interesting charts.
https://www.footballoutsiders.com/stat-analysis/2018/2017-adjusted-games-lost
Long article but worth a read, and maybe a check back later in the season to see how your team fared as they also compare to actual performance which makes for interesting charts.
https://www.footballoutsiders.com/stat-analysis/2018/2017-adjusted-games-lost