Multiple tab lookup - Multiple criteria

[Tom1989]

Hi,

I have a spreadsheet with a tab for each month of the year, and a summary tab in which I intend to collate the data. The summary tab needs to be cumulative and so will need to look at one extra tab at the end of each month. Currently in my summary tab I enter the month in cell A1, and in cell A1 I have a formula which reveals the month depending on the date (for example, January and February currently show as "Feb" but each of the other months currently show their month, when we hit 1st April Jan, Feb and Mar will show "Mar").

To add to this we have multiple sites and multiple cash splits to allocate to. So essentially I need a formula which looks up the month in cell A1 across the monthly tabs, looks up the cash split and then returns a cumulative result. The columns will not change over the year so there is no need to put a lookup on the plant name, it can just sum the same column across each tab.

I have attached a dummy file to hopefully illustrate my point a bit better. Essentially what I am looking to see in cell C4 on the check tab is any "Growth" projects which relate to "Site 1" for Jan and Feb, but will then change to Jan, Feb and Mar when I change cell A1 to read "Mar" next month.

Thanks!