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‎Sep 05, 2023 07:23 PM
Hello all,
Brand new to Airtable and like what I see so far.
I am trying to calculate a date from two sets of data. In Excel I would have use Start Date + Duration - 1 to get the End Date.
I thought I would use the Datetime_Format, but I am getting an #error! I wrote DateTime_Format({Start Date1}+{Duration}-1, 'M/DD/YYYY')
The Start Date1 is formatted as a Date US (9/5/2023)
Duration is a LookUp field pulling from another tab in same base that is formatted as a number.
I know this is probably something simple, but any help would be appreciated. Also, a good recommendation for Airtable Resources. 🙂
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‎Sep 06, 2023 02:22 AM
Use the DATEADD() formula. You need to specify what unit of time the duration is.
DATEADD({Start Date}, {Duration}, 'minutes')
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‎Sep 06, 2023 08:33 AM
Thank you, I have a date now instead of an error, but it is not the right date.
For example, the first line in image, should be (1/1/2024 + 9) - 1 = 1/9/2024.
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‎Sep 07, 2023 02:38 AM
I'm not sure what can have gone wrong there but it seems to be subtracting 1 day instead. Try using an intermediary Duration formula field:
{TD Work Days...} - 1
That should equal 8 for the examples you have posted. Then do the DATEADD formula using this field.
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