If you are wishing to recalculate the values of all your records then you can do the following:
Tick the checkbox to the left of the column headers on the list view
A message will appear "You have selected 20 records in this view. Select all records in the result set"
Click Select all Records
Select Recalculate Values from the dropdown list attached to the checkbox that you ticked in step 1
Once 1000 records have been updated, sort the list view by Date Modified by clicking on that column header. Ensure oldest records are at the top
Repeat steps 1-5 until all records show with a Date Modified of today