I'm trying to get the sum of dollars spent in each week of the year. The range is compiled of invoice data, with non consecutive dates. Column A contains dates, and column G shows the corresponding dollar amounts. I want to return the total dollars spent for the first week of the month in cell E20. (I will end up having all the weeks of the year listed with the dollars spent in that week.) Should this be a SUMIF function, and how should dates be entered into the formula?