SumIf with variable columns

Hi all.
I have a budget tracker with a summary page.
On the summary page I have a rolling Actual cost column, This should add up all the months previous costs.
I am at Month 5 (May), I want a formula to add all the cells in columns 1,2,3,4 and 5.

Currently I have:

=SUMIF(Tracker!$C$4:$C$29,Front!C4,Tracker!$E$4:$E$29)

*Where Tracker is where data is held and Front where data should be produced.

I am wondering if a Index formula would be needed though have little experiance in this.
My aim is to show Actuals to date as well as forecast, having a formula for Actuals would help with forecast.

Thanks for aby help.

example provided: