How to create a new date field based on a formula

[MaryB]

In my data source I have a date field. I'd like to create a new field that is also a date but changes the month. For example in my Original Date field I have 6/1/15, I want my new date field to be 5/1/15 (a month behind).

Is this possible? I assume I can do this with the Formula module but not sure how to write this.

[michael_treadwell · Accepted solution]

Try the DateTimeAdd() function in the Formula tool

DateTimeAdd([Date], -1, 'month')

See attached

[MaryB · Accepted solution]

I was able to get this to work with the following formula:

DateTimeAdd([Date of Assessment],-1,"months")

[MaryB]

Thanks!