Unpivot Cashflow Data for 140 month project

Hi Everyone, I am fairly new user to the amazing PBI software and needs some advice on best way to unpivot an Excel cash flow data model into  PBi for reporting.

Here is the Excel source data and PBI data results i have imported.

Excel Raw Data Example

PBI Imported Data

I beleive the main issue is when i try to unpivot the Date (shown in ROW 1) and value (shown from Column5 onwards).

How should I unpivot the data so i get the dates and values per the First 4 rows. Initially, i tried to unpivot from Column 5 onwards but the results dont look right to me. Should I unpivot from Column 2 instead?

Do i also need to replace the dashes with zero values too?

Can anyone give me some pointers on how to properly unpivot this data for reporting.