On Jan 11, 1:22*pm, Shane Devenshire
wrote:
PI has been calculated to 2 billion digits, probably more by now,
but Excel is not prepared for more than 15. *
Also, although this is not the core problem, computers work in
binary, we work in decimals - which leads to approximations.

In Excel 2003, the binary representation of PI() is exactly
3.14159265358979,311599796346854418516159057617187 5. According to
online sources, the value of pi calculated to that many decimal places
(plus 2) is 3.14159265358979,323846264338327950288419716939937 510.
(The comma marks 15 significant digits to the left.) I'm too lazy to
compute the percent error :-).