Duh! Problem Solved!

I knew it was something simple. I knew it worked before, as written.

The problem turned out to NOT be with my macro but with the data file. Actually, I guess it was technically the macro. The Average function bombed, if there was no data in the columns. At work, I used actual data file which was many hundreds of megabytes. At home, I used a newly created file, that didn't contain data in all columns.

If I actually have data in all columns, the macro works as written. I guess I could use another AVERAGE function to disregard bad data.

The macro works as written and references in other workbooks can be used as written.

Thanks to those who helped.