More Than 7 Nested If -Then - Else Through VBA

My objective is to replace a text string with a numeric variable. The string has text values such as US, Canada, Germany, France etc, There are about 15 such words in total. Each row will have a different one of the 15 text strings.

Each text string has a corresponding number, which I want to use in various formulas throughout the spreadsheet. The numbers are located on a separate worksheet (“Match Rate”), within the same workbook. I obtained the numbers from a formatted report, which I simply pasted into the second worksheet. Due to the complexity of the report, I can’t reformat the numbers to allow use of the VLOOKUP function.

I created the following function, but unfortunately it doesn’t work. Can you help, please?

I’d like to stay with a VBA solution, since a simple if/then sequence such as this is an excellent introduction to the powerful world of VBA... (it just doesn’t work, yet). I suspect the problem is in the calls to the Match Rate Worksheet.