Granted, it's the time of the year before most teams have filled up their 40 man rosters with minor leaguers to protect them from the Rule 5 Draft (who skew younger) and free agents (who skew older and who are more likely to have been born in the 1970s or earler). Still, I wondered if there were any other teams who had no players born in the 1970s and/or had multiple players born in the 1990s. Below is a breakdown of each MLB team's 40 man roster by decade of birth.
Notes: 40 man rosters as of November 11, 2011. I added the Papelbon and Carroll signings since their deals were announced but had not been added. Juan Uviedo (Marlins) and Ronald Belisario (Dodgers) aren't counted as they are on the restricted list.
A few interesting observations:
Kansas City is the only other team with no players born in the 1970s or earlier other than the Jays. While it's somewhat surprising for any team not to have at least one guy aged 31 or more, it makes sense that the other team besides the Jays would be Kansas City given the youth movement/rebuilding process there.
Atlanta and Washington have the most 1990s players on their roster, with 3 apiece; other than the Jays, only Boston KC and Houston have multiple players. Exactly half the league does not have a single player currently there.
New York is the only player with a player born before 1970 - he of the ageless cutter, Mariano Rivera.
Since the majority of the players were born in the 1980s (which would put them at 22 to 32 years of age, roughly within 5 years of peak performance on either end), I further subdivided the 1980s players into two halves:
Not only does Toronto have no players over 31, among the players born in the 1980s, the distribution again skews towards the younger side. In fact, the Jays have the 3rd highest proportion of players born in 1985 or after on their 40 man roster, with only KC and Cleveland surpassing them:
I've highlighted the 2011 playoff teams, and unsurprisingly (to me at least), six of the ten teams with higher proportions of "older" players (essentially at or around their peak performance years or past them) made it to October. Playoff teams generally have higher payrolls so they can afford free agents, and have more need for veteran roleplayers. I was somewhat surprised to see Tampa Bay there, but they have a large number of players on either side of the 1985 cutoff and they also tend to be more conservative in promoting prospects which generally makes them older relative to other players on other teams with similar service time.
Finally, just for the heck of it, I ran a correlation between 2011 wins and % of players born 1985 or after, displayed below. The trend is fairly evident, but this is definitely a case where the "correlation is not causation" caveat applies. While good teams generally have more veterans, it would be folly to go on a signing spree thinking it will automatically bring in more wins (this might be a cautionary tale for the Miami Marlins given thier interest in almost every free agent).
I probably got a little carried away by this, and as noted above, this is a rather unsettled time to be looking at the 40 man roster. I obviously don't expect the Jays to go into 2012 without a single player aged 31 or over (bullpen additions like last year, backup catcher, etc), but I still think it's indicative of the direction in which this team is going. The Jays have one of the youngers rosters in MLB, and with possible midseason promotions in 2012 could possibly get even younger.