A recent blog post by NFLLabor.com dissected the player's claim that NFL careers, on average, lasts just 3.5 years. Steph Stradley picked up on it over at her Chronicle blog, noting that this is just the latest thing that the NFL and (not anymore) NFLPA can't agree on.
↵↵↵Clearly, the NFL and the NFLPA are measuring two different things. Just observationally, in recent years, the trend has been against veterans on rosters and not just due to injuries. Younger players are cheaper. Vet minimums are higher than for younger players. Expensive players get cut if they don't play to their contract or won't agree to a pay decrease. If your team has expensive vets, younger players fill in.
↵These numbers don't take into account the sizable number of players that do not make rosters. The term "accrued season" is relevant for players/teams because it can determine when a player is eligible for free agency. So a lot of the players on the above list have zero accrued seasons which pulls down the numbers.
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As usual when you're running statistics in the middle of a PR war, both sides have started out with the context and colored the numbers to match it. The truth is probably somewhere in-between the two claims. The number probably shouldn't include all players who ever get signed to a contract, because a small minority of them are purely practice squad talents that won't ever get put on the roster. At the same time, some players don't accrue seasons simply because they get hurt and the NFL doesn't have large enough rosters to accommodate them sitting on the IR.
↵What does it really all mean? We need to send the two sides to binding arbitration with Nate Silver looking over the data.
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