Born in August? Welcome to the Majors

Fun fact: since 1965, players born on July 31 have spent a combined 30 years in the Major Leagues. Fast forward 24 hours to August 1, where players born that day have spent a combined 71 years in the majors.

How could 24 hours make such a difference?

It has been argued for some time now that the month in which you are born could have a significant impact on your chances at making it to the big leagues. Immediately, people look at Alex Rodriguez, born July 27, and say that July can’t possibly be a bad month to be born in. I mean, after all, A-Rod’s one of the best of all time.

But let’s not get too caught up in the stars.

Using information from Slate.com, we find that there is, in fact, a strong correlation between the month you are born, and your chances at making the Majors. The reason is more difficult to uncover, but splitting up American born and non-American born players gives us a very important clue.

Consider these two graphs, one showing American born players in the Majors, and one showing non-American born players:

The American born graph shows a strong correlation between month born and players in the Majors. The graph is highest at August, and has a general decline as it approaches July. The non-American born graph, on the other hand, shows no correlation whatsoever.

Thus, we can conclude that the month debate is strictly an American issue. That is, something specific to this country — culture, policy, etc. — causes players born in August to have a much higher chance at making it to the Major Leagues.

Go back to the opening fact, that players born on August 1 have an incredible advantage over players born just 24 hours before them. That magical date, August 1, gives us a clue as to what is causing this startling pattern.

Since the mid-1900s, all American non-school affiliated youth baseball leagues have set the cutoff date at July 31. Little League, Cal Ripken/Babe Ruth, PONY, and multiple other youth leagues use the same cutoff date. Latin America, however, has no such rule.

Consequently, the oldest players in almost every American youth league are those born in August, while the youngest are those born in July. For example, a player born on July 31 will be the youngest player in a given league his first year, and of average age his second year. A player born on August 1 will be of average age his first year, and the oldest his second year.

That 12-month advantage cannot be denied. Especially in a youth league, when kids are at the height of their growth, a 12-month head start will make a kid stronger, faster, and thus far more athletic and valuable.

Coaches, eager to win, are undoubtedly going to focus on such kids. The older, stronger kids will start more, get more opportunities at higher demanding positions such as pitcher, catcher, and short-stop, will rarely sit on the bench, and will be in the spotlight for most of their youth. How could that kid not love baseball and want to pursue it as a career?

So if your dreaming of your kid under the grand lights at Yankee Stadium, with crowds of 50,000 chanting his name, you better plan early.

Jess is the host of The Seamheads.com Radio Hour , which airs every Monday at 9pm, Eastern. You can follow him on Twitter , check out his Web site , or contact him at jess@jesskcoleman.com .