I get a little nervous with immobile quarterbacks. When a player isn’t doing anything as a runner, it makes it harder for him to stack up statistically against the more mobile players at the position.

With rushing production tending to be worth about twice as much in typical fantasy scoring systems, it’s a huge edge to run for 700 yards. That’s statistically equivalent to throwing for 1,400. If a player runs in 6 TDs, that’s like throwing 9 touchdowns.

Many times over the years, I have noticed quarterbacks like Philip Rivers and Eli Manning seeming to have had good seasons, only to show up in the teens via the numbers – in large part because of their limited mobility.

So as I put together my own draft board, I tend to be leery of the pocket passers who don’t much with their legs. Guys like Matthew Stafford (pictured), Derek Carr, Kirk Cousins and Matt Ryan. There will be passing yards and touchdowns, but it will be offset somewhat by the lack of anything on the ground.

It’s tough for those kind of quarterbacks to get in my top 5.

I played around with some numbers on this. I pulled up the stats for the last 20 years for all quarterbacks who started at least half of a season – about 650 quarterbacks.

There were 127 quarterbacks who averaged fewer than 5 rushing yards and didn’t score a rushing touchdown all year. Only 17 of those quarterbacks (about one per season) finished with top-5 per-game numbers. Another 20 finished in the back half of the top 10 (again, using per-game numbers).

The other 90 didn’t finish with top-10 numbers. (Many of those quarterbacks, of course, weren’t just unproductive runners but were also lesser passers.)

I’ve got the 37 with top-10 numbers listed below. Stafford is on it twice, with his two 40-touchdown seasons. He was the No. 5 quarterback in 2011 (using per-game numbers). Despite his huge passing numbers last year, he finished as just the 9th-best quarterback per game.

2008Drew Brees, N.O.163172.130.0024.31
2004Peyton Manning, Ind.162853.062.0026.72
2005Marc Bulger, St.L.82871.754.0021.72
2014Peyton Manning, Den.162952.44-2.0024.63
2010Peyton Manning, Ind.162942.061.0023.13
2006Drew Brees, N.O.162761.632.0020.83
2010Drew Brees, N.O.162892.060.0022.74
2009Matt Schaub, Hou.162981.814.0022.64
2008Kurt Warner, Ariz.162861.880.0021.84
2003Peyton Manning, Ind.162671.812.0020.94
2011Matthew Stafford, Det.163152.565.0026.75
2014Ben Roethlisberger, Pitt.163102.002.0024.05
2017Tom Brady, N.E.162862.002.0022.75
2010Philip Rivers, S.D.162941.883.0022.75
2009Peyton Manning, Ind.162812.06-1.0022.25
2007Kurt Warner, Ariz.112582.091.0021.45
2005Peyton Manning, Ind.162341.753.0019.05
2015Ben Roethlisberger, Pitt.113241.643.0024.36
2017Ben Roethlisberger, Pitt.152831.873.0022.26
2008Tony Romo, Dall.132652.003.0021.66
2012Peyton Manning, Den.162912.310.0024.07
2006Marc Bulger, St.L.162691.503.0019.87
2015Eli Manning, NYG162772.194.0023.08
2013Philip Rivers, S.D.162802.005.0022.48
2016Philip Rivers, S.D.162742.062.0022.28
2009Brett Favre, Min.162632.060.0021.48
2004Brett Favre, G.B.162561.882.0020.88
2007Brett Favre, G.B.162601.751.0020.18
2006Carson Palmer, Cin.162521.752.0019.88
2021Matthew Stafford, LAR172872.413.0024.39
2017Philip Rivers, LAC162821.750.0021.19
2016Derek Carr, Oak.152621.875.0021.710
2013Tony Romo, Dall.152552.073.0021.510
2004Brian Griese, T.B.102471.902.0020.110
2007Carson Palmer, Cin.162581.631.0019.510
2003Brett Favre, G.B.162102.001.0018.810
2005Kurt Warner, Ariz.102711.103.0018.210

—Ian Allan