Decimal places for frame interval

Hello, I found that there is a slight difference in edge velocity when I run a script for batch processing.
It is caused by the limited decimal places for frame interval that I put at the start dialog panel.

The script calculates the edge velocity using a time interval of 0.0116 but the value is rounded to 3 decimal places, 0.012, at the dialog panel, which results in about 3% difference.

Is there a way to increase the decimal places for the frame interval at the start dialog panel?
Thank you.