Calculation Function In A Report

[scubagal]

I created a simple report in Access 2010 that in one column lists the date with a column beside that lists a numeric reading for that date. Now what I need to do is make a calculation that subtracts 1 reading from the previous reading and dispalys it beside of the first date. Example:



Date Reading 24hr Difference

11-1-11 123456 333

11-2-11 123789 174

11-3-11 123963

Is this possible? Thanks for any help.

[alansidman]

Look at this link on Allen Browne's site.

http://allenbrowne.com/subquery-01.html

Alan