Why do we lose counts through a timed loop?

I have written a program to count the rising edges of a square wave produced by a function generator using the DAQmx functions. The counter is read in a time loop with a period of 1 second, so we take a sample once every second. It appears that the program is working correctly accept for the fact the the counts are continuously 2% lower than they should be. We are guessing that this is due to the fact that the timed loop really isn't taking a full second to complete each iteration. Any suggestions on how to fix these timing errors? The counters are read from the NI 6608 Device if that is of any help.

Please post images of your code so that we can be off assistance.
Thank you,
Ben
Ben Rayner
I am currently active on.. MainStream Preppers
Rayner's Ridge is under construction

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clip_image0011.gif ‏15 KB

Your data is U32 (unsigned integer) which does not have negative values. According to unsigned integer math, "negative" results will wrap.
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Why do we lose counts through a timed loop?

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