Hello AlenaNR,
Basically, 00:00 is valued as 0 and 12:00 is valued as 0.5. Time counts up the hours and restarts at 0 when you reach midnight. The way around this is to use dates along with the times. Each day is valued as 1. Adding 1 to a date results in the following day.
| Example: Now() results in something like this, where the whole numbers is the number of days and the decimals are the hours/minutes/seconds. 45085.77027 |
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Set your formula to add 1 when the end time is past midnight, but before the start time.
| Example: =(EndTime - IF(StartTime>EndTime,1,0)) - StartTime |
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