Why do you need 2 columns for "Del" and "ADD"?
When for every row you use only one, then those values can be in same column.
When you are using both of them in same row, then taking into account they add and delete 1, which results in no change at all, so you can left both of those sells empty with exactly same result.

And use tables for data entry - enter table header at top, and data into according rows below header row. This helps you to keep your data organized, and when you look at then after a couple of months later, you'll know what it is about.
An even more advanced approach is to define the data organized in this way as a Table. Then you can use Table syntax formulas, which are expanding automatically whenever you enter new data into defined Table.

Another advice is never enter any initializing values (1000 in your example) directly into table. This can mess up with your formulas, and this isn't obvious at first glance, from where this value is gotten.

Added is an example!

Attached Files

CountingTableExample.xlsx (12.6 KB, 9 views)