Locking values

Hi,
How can go about the following?

I have a worksheet with a macro that when clicked will update a data w/sheet with that months data.
I then have an output w/sheet that displays the data in monthly columns.
The problem is every time I run the macro to get the latest months data
it changes the previous months data in the output w/sheet as well eg When I run the maco in August it also updates the column for July. I know I can lock the cells but can I lock the values so they dont change for July?

Or can anyone suggest a more robust way of doing this?
I've thought about doing some tedIous macros that will copy/paste/tanspose the values but like I said tedious.

Example s/sheet provided for the interested...