Count Number Of Columns

We have a sales table that 23 sales people update then send back to me. So each week I receive 23 worksheets.

The number of columns in the tables I get back can vary, depending on what each salesperson is reporting for that week.

I have written a macro that takes each sheet, automatically finds the last column and then adds two new columns of summary data.

I use COUNTA on the header row to find the number of colums. This usually works fine - but there is one problem that can occur.

Sometimes people insert one or more blank columns in the table. So how can I find the last column, because COUNTA won't work? (I do not want to simply delete these columns because some people have set up vlookups and their own macros based on the position of the columns they have defined, including the blanks.)