Ok I can't attest to the credibility of this here.........but it's pretty ironic......
"The primary purpose of the DATA statement is to give names to constants; instead of
referring to pi as 3.141592653589793 at every appearance, the variable PI can be given
that value with a DATA statement and used instead of the longer form of the constant.
This also simplifies modifying the program, should the value of pi change."
- FORTRAN manual for Xerox computers