Q:
A: Wasn't it 1900? That's my guess, seems to me it was a nice even figure like the turn of the century but I wouldn't swear by it.\ EDIT: I was going to come back and mention that it would depend on if you wanted to know when it became the 50th state or when it became a US territory. It became a US territory in 1900 but was admitted to the union as the 50th state in 1959