I have a worksheet that has 100 tables consisting of dates and injection
rates. The tables do not all start on the same date, but I need to have
totals for each date and I'm not sure how to do this. I've tried a couple
things but nothing is working. My worksheet looks like this:

Well #1 Well #2
Date Injection Date Injection
10/1/2001 1 1/1/2002 0
11/1/2001 2 2/1/2002 1
12/1/2001 3 3/1/2002 4
1/1/2002 4 4/1/2002 3
2/1/2002 5 5/1/2002 0

I have 100 tables like this that each continue on for 50 years and I need to
sum up all the injection data on the same dates, so ultimately I can find the
total injection for the whole field. I've tried SumIf already and I just
can't figure out how to find the injection data from every table. If anyone
has any ideas I'd greatly appreciate it!