My first query challenge was how to make a running total query. Michael Levy and Ed Pikman answered that one. Now I need to do the opposite. I am receiving data consisting of running totals of expended hours. I would like a query that extracts the amount expended each week. For example, if my data looks like this:

4/5/98          100
4/12/98         105
4/19/98         120
4/26/98         130

...I would like a query to return this:

4/12/98          5
4/19/98          15
4/26/98          10

If I have to, I will, once again, write a procedure to scan the table and write the cursor, but it would be nice to make it with a SQL SELECT.

Thank you.