Using column header as values for calculation

Anonymous 

here is a workaround for you.

1. create a reference table , user hearder as first row , transpose table and remove text value.

2. create a column in original table

Column = CALCULATE(COUNTROWS('Table (2)'),FILTER('Table (2)','Table (2)'[Column1]<'Table'[nextorderyear]))

pls see the attachment below