Help, how to get tags recalculated

I have 7.0.1 installed and added number of profile records and put all the dates to current date time.  How do I get the tags to be recalculated?  I can go and change one record using regular login and after saving that records tags are calculated but the rest are not even if I change all the date time fields to the same or past the date time of the record that was changed using the system.  Thanks in advance.