how to deduct half a day from a nonworking day

Hi Time Expert,

We have configured a sub-type counting non-working days.

When this absence is calculated over a half-day of a nonworking day, the system counts down a full day.

Example :
Considering that Sunday January 23, 2022 is nonworking, we wish to ask for a calendar absence from 8:00 a.m. to 12:00 p.m.

How do I get the system to count 0.5 days instead of 1 day?