I have a spreadsheet with multiple worksheets. Each worksheet has a
date column and an amount column which are adjacent (column F and G).

I would like a summary worksheet that adds up the amounts for each
unique date from each worksheet.

For example if worksheet 1 had

Jan 1 $100
Jan 2 $50
Jan 10 $100

and worksheet 2 had
Jan 1 $5
Jan 3 $10
Jan 10 $100

The summary would look like
Jan 1 $105
Jan 2 $50
Jan 3 $10
Jan 4 0
Jan 5 0
Jan 6 0
Jan 7 0
Jan 8 0
Jan 9 0
Jan 10 $200

I beleive this uses the lookup function. Also, if I were to add
worksheets would there be an easy way to update the formulas? Curently
I have about 150 worksheets within the one spreadsheet.

Thanks,

Robert