It seems pretty obvious that the ideal situation to kick in would be inside of a dome, but how much more accurate does it make kickers?
Over the past five seasons, from 2010 to 2014, there were five domed stadiums in play: Atlanta, Detroit, New Orleans, St. Louis, and Minnesota (excluding 2014). We’ll ignore retractable roofs for this study.
There was an average of 995 field goal attempts each season in the NFL, which comes out to about 31 per kicker.
Field goals in our focus group—those kicked in domes—had an 85.8% success rate (601 of 700). Those kicked in the non-domed stadiums had an 83.6% success rate (3575 of 4276).
So yes, our prediction that kickers would be more accurate in domes does appear to be true. The catch is that they were only 2.2% better than non-dome percentage. If kickers attempt 31 field goals in a season, being 2.2% worse is affecting just over half of a field goal.
I would take any extra advantage I could get, but over a season three points is not a whole heck of a lot.
Appendix: Fantasy Football
An oft-repeated bit of advice in fantasy football is to grab a kicker who plays in a dome, based on the aforementioned thinking that kickers in domes are more accurate. As we just saw while that is technically true, it won’t have much affect over the whole season.
The bigger fault with this thinking is that team offenses have a much larger effect on kickers than the stadium. It is odd that this thinking persists when the kickers in domes over the past three years have finished in these positions among kickers with standard fantasy kicker scoring: 1st, 3rd, 4th, 5th, 16th, 17th, 18th, 20th, 22nd, 22nd, 24th, 29th, 34th.
The top three, with the first, third, and fourth rankings were Blair Walsh, Matt Bryant and Jason Hanson, but nobody would have been able to take advantage as all three had those outstanding seasons in 2012.