Hi Sounds like a problem that involved a continuously running clock that incremented a floating point accumulator. When it started to saturate in about 18 days, they were no longer able to calculate differential time. Oh my, why didn't the missile fire? Here is another one. I wish to do multiple precision but all I have is a standard compiler that only does 32 bit math. I write some utilities that allow me to handle the simple task of extending the operations such that I can do a 64 bit integer divide by a 32 bit number. I was careful to only do integer operations! When I apply this new math to a XY table control, I notice that right in the middle of the table, as I step along, it jumps. Careful measurements of the size of the jump correspond to one LSB of the upper 32 bits of my multiple precision operations. So, what is wrong here? I also notice that the center of my XY table is coordinate 0,0 ( hint ). Dwight