Birth Order & Occupation

I’d like to know if there is any connection between birth order and choice of occupation later in life. I’ve read that most U.S. presidents were firstborns, but this might not be that surprising when you consider that almost all of them were WASP’s who tend to come from smaller families. Are there any studies that have shown that members of a particular profession are disproportionately firstborns (or lastborns)?

I was hoping for something factual, like “70% of physicians are firstborns, whereas only 30% of the general population are firstborns.” I realize that even if such a link were to be established, we still wouldn’t know if it was because firstborns are more “goal-oriented” or if it was due to parental favoritism toward firstborns in allocating time/resources. But it would at least be a start.

I’m not sure if anyone has posted actual percentages on the internet, but there are several sites that make generalized pronouncements:

Ohio State University Extension Fact Sheet - Birth Order
Birth Order Research (A print and net bibliography)
Birth Order: Science or Myth? (A contrary view)
Birth Order Affects Career Interests
Why Do People Believe that Birth Order Has (Another skeptical view)

Why assume, when the facts are available?

10 siblings:
James Buchanan

9 siblings:
Benjamin Harrison (+ 2 half-siblings)
James K Polk

8 siblings:
Millard Fillmore
Zachary Taylor
Grover Cleveland
John F Kennedy
William McKinley
Thomas Jefferson

7 siblings:
James Madison
Warren G Harding
John Tyler
Chester Arthur

6 siblings:
Dwight D Eisenhower
Franklin Pierce (+ 1 half-sibling)
William H Harrison

5 siblings:
George W Bush
George Washington (+ 4 half-siblings)
Ulysses S Grant

4 siblings:
Richard Nixon
James Monroe
George Bush
Martin Van Buren (+ 3 half-siblings)
James Garfield
Theodore Roosevelt
Lyndon B Johnson

3 siblings:
John Quincy Adams
William H Taft (+ 2 half-siblings)
Jimmy Carter
Woodrow Wilson