posible, but not that simple.
you would need a new field to record when the specific field is updated.
then add a lookup recordset to look up the value that is being passed for that filed on the update. if the lookup recordset count returns 1, then the value is not changed, don't change the date for the tracking field. if the look up recordset count returns 0, the value has changed, so update the date in the tracking field to todays date.
if you need help setting this up, we could help through a premiere support appointment: