Convert Variable Column Data Report To Stack The Data Into Just Three Columns

Hello,

I have a payroll data report as per sheet 1 on the attached file, where each payroll number has its value per wage type in each column.

I want the data to be stacked just in columns A, B and C as per the sheet I have manually produced on sheet 2.

The example file has a small amount of data so you can see my problem.
The real file has about 100 columns and about 1,000 rows and the number of columns and rows could be variable on file.

If someone could advise some vba code that could convert the data on sheet 1 to appear as per sheet 2 it would be appreciated.

Thank you