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## Subtract business hours from timestamp

• #### 1.  Subtract business hours from timestamp

Posted 15 days ago
Edited by Jen Hamilton 15 days ago
I have a time stamp field called "Deadline" and I want to subtract business hours from it (weekday hours.) How?

This doesn't work, it just knocks the result to a Friday if it falls on Sat/Sun.
Subtracting 36 business hours from an 8am Monday deadline should return Thursday at 8pm, not Friday at 8pm.

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Thanks,
Jen Hamilton
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• #### 2.  RE: Subtract business hours from timestamp

Posted 14 days ago
I had to do something similar (calculate using working hours and not just regular hours).  The way I did this was by creating a very complex set of variables and if statements that increased the hours to subtract depending on how to take into account the non-working hours.   In my case this was in a single day so I only had to take into account an 8 hour work day.  But you could do something similar using "DayofWeek" for your problem.   It's brute force, but it works.

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Andrew Patricio
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• #### 3.  RE: Subtract business hours from timestamp

Posted 14 days ago
I thought that might be the answer. I often feel like I'm making things more complex than they have to be, "WeekdayAdd" works so well on dates that I hoped there was an easier answer.

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Jen Hamilton
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• #### 4.  RE: Subtract business hours from timestamp

Posted 14 days ago
Jen,

Assuming:
• that you never exceed one weekend
• Deadlines are on the whole hour
• The amount of time you are going backwards is whole hours

Try this:

// Convert User Numeric Input to Duration in Hours
var duration SubHours =Hours([Hours]);

// Calculate Day of the Week from the Deadline     Sunday = Day Zero, Saturday = Day Six

// Calculate the numerical  Hour of the Day from the Deadline

// Calculate Hours from Sunday