Copy and Paste based on a hlookup

Hi,

I need to create a macro that will look at a user selection of the month and then copy the actuals to date that match that selection and overwrite what is in as forecast.

I have attached a two tab example of what I mean. Basically in sheet 1 there is forecast for the year on the left and then actuals for the year to date on right. On sheet 2 the user will select which is the latest month they have actuals for and then they can press a button and all the actuals will over write what is in the forecast.

Some limitations are I don't want any months that are still forecast to be overwritten and there will be further information down below so can't copy the entire column has to be limited to a certain number of rows.

Any help is greatly appreciated as I have been going around in circles on this one for a while...

Thanks,
Tony