Six years ago, I took my first crack at analyzing field goal kickers. I have been meaning to update that article for each of the last three offseasons, and with the sun setting on the 2015 offseason, I didn’t want to let this slip yet again.

Ranking field goal kickers is not difficult conceptually, but it can be a bit challenging in practice. One thing I’ve yet to refine is the appropriate adjustments for playing surface, stadium, time of game, temperature, and wind. That’s a lot of adjustments to deal with, all on top of the most obvious adjustment: for era.

But as I understand it, Rome was not built in a day; further, I believe that a journey of a thousand miles begins with one step. As a result, I’m okay with only getting part of the way there for now, and punting (which is very, very different from kicking) the rest of this process to next offseason.

Let’s begin with the obvious: era adjustments are really, really, important.  To provide some examples, I looked at the field goal rates at four different increments: 22-24 yard kicks, 31-33 yard attempts, kicks from 40-42 yards away, and finally, field goal attempts from 49-51 yards.  In the graph below, I’ve plotted the success rate at those four distances for each year since 1960, along with a “best-fit” curve at each distance. Take a look:

Here’s the mind-boggling fact: kickers are more successful from 49-51 yards today than they were from 22-24 yards in the early ’60s. Even with the introduction of Pete Gogolak and the soccer-style kick, the increases here were largely gradual.

I ran similar regressions for all distances, and well, take a look at the smoothed lines here:

From here, all we need to do to rank kickers is compare their actual performance for kicks at each distance, and compare how they did relative to league average. Check back tomorrow for that.