You should increase the time, with 20 seconds there is not a big difference between 0.031250002 and 0.03125, only few more integers incrementation.
(20/0.031250002 VS 20/0.3125)
You should probably go for 100 seconds, or even 1000 s
(you can launch a lan game, this way you won't have to wait, you can minimize wc3 and let the test continue alone).
But for now, it seems that the number under the decimal doesn't matter, unless you are using more than 9 numbers under the decimal, then the period is fucked up.
You should also probably test the same way i did, since i've found that only 8 numbers under the decimal was taken in consideration for periods.