How to automatically insert a blank row after a group of data

Question

I have created a sample table below that is similar-enough to my table in excel that it should serve to illustrate the question. I want to simply add a row after each distin

Answer 1

1. Insert a column at the left of the table 'Control'
2. Number the data as 1 to 1000 (assuming there are 1000 rows)
3. Copy the key field to another sheet and remove duplicates
4. Copy the unique row items to the main sheet, after 1000th record
5. In the 'Control' column, add number 1001 to all unique records
6. Sort the data (including the added records), first on key field and then on 'Control'
7. A blank line (with data in key field and 'Control') is added