How to add multiple column cells based on date

Hello
I am trying to find a way to show forecast to date.
If I have multiple columns showing forecast per month (Jan-Dec), in the totals column, I want to show what is the current forecast to date depending on a date I choose.
So If I choose Jan, it should show just Jan, if I choose Feb, it should show Jan + Feb

thanks

Thanks, see attached

That does seem to work!
Thank you very much!

1 follow up question I have.
If I added 1 more column to the end called FY Forecast, this would show the actuals + forecast for the year. But if I choose March, it would show only the actuals for Jan, Feb and March and the Forecasts for April to December.
Can that be done at all?

If I wanted to summarise this in a front summary sheet, based on totals for all projects say, how can I do this?
See attached for an example

Hi
I have amended a little
Basically on the front sheet, I would like a formula which finds Programme 1 in the work tabs (I have over 100 programmes), all would be named in the front sheet)
Depending on the month chose in the front sheet, it should show the total forecast.

So for example, in the attachment, for Programme 1 on the front sheet, choosing February, should give me a forecast of 34 in the Front worksheet. (this coming from the programme 1 tab cell f14.

If I chose March, for Programme 2, I should get 36

Thanks

Hi
Also, I have come across an issue with the formula:

=SUMIF(OFFSET($B$20,,,,MATCH($A$2&$AM$20,$16:$16,0)),$AM$20,OFFSET(B21,,,,MATCH($A$2&$AM$20,$16:$16,0)))

going back to the spreadsheet you kindly attached in an earlier message, I can see that if there were prior months in previous years on the same row, the forecasts / actuals etc would be calculated as well.

So where we started with January in cell c3, on my work I have previous months of other years, these are calculated in the totals tho

thoughts?

Thank you
Going back to the earlier question in post 10.
=SUMIF(OFFSET($AL$20,,,,MATCH($A$2&$AI$20,AM$16:BV$16,0)),$AI$20,OFFSET(AL21,,,,MATCH($A$2&$AI$20,AM$16:BV$16,0)))
I have solved the issue of the totals returning figures from previous years.
The issue I now have is that the above formula misses out on the last 1 or 2 columns.
Will try ands create a sample spreadsheet to show you

See here:
In cell BX 21, I expect to see 55.
This is based on looking at Nov'18 to Sept'19
Dates are from cell a2

for some reason, I am getting 50, so it seems to be missing the last column (in this case September)

Thoughts?