Calculate a date field that is 90 days earlier than the one chosen

I am trying to calculate a date field that is 90 days earlier than the one chosen.

A Bride chooses a date of say 1st MAY 2016. The cost of this wedding needs to be paid in full 90 days before the event date.

In a hidden field, I would like it to populate with the date that is 90 days previous than the one the bride inputted in the date field.

The date in the hidden field for the example above would show 1st February 2016 9 Or there about’s give or take.

You can calculate a date 90 days earlier than the one chosen by performing a calculation with the Form Calculation widget: http://www.jotform.com/help/259-How-to-perform-calculation-in-the-form 

Example:

Result:

Let us know if you need more help, we will be glad to assist you.

this doesn't work :(

@davidgrayvideos

My colleague already answered you on this thread: https://www.jotform.com/answers/1056149

Please reply there if necessary. Thank you.