I ran into the same problem and used the recommended code. But for some reason, it will accept only May month dates and the calculations are correct. Any other dates besides a May date, the calculated fields returns January 1, 1990.
I am attempting to add a date field and then have a another field add an amount to a box if the date is less than 30 days. Later I want to update the form to have the today's date is less than 10 days.
Early Registration Fee is $10.00 if posted by February 25, 2008
Late Registration Fee is $20.00 if posted by March 17, 2008
It seems simple, but, when you get to be 71 years old, it seems difficult. Any help will be appreciated.