Pivot table- adding a column

This is probably extremely easy but I can't get it to work so your help will be very much appreciated.

I have a pivot table with 4 columns (Name,unique number, signing and Sales)

The pivot is generated from our global database. The sales column updates but it is severely delayed and we know the sales figures before being updated. I need to add a column with our sales figure and another column with the difference between the two. The only trouble is, when the pivot table is refreshed and new customers have been added, all the date falls into the wrong rows. Making sense? How can I get the 2 new columns to be in sync with the pivot table?


Thanks,

Ben