Number of coins I have? [solved]

When looking for a specific coin yesterday, I noticed that I had made an error in the number of coins I had entered into the specific quality box. I had entered 11 instead of 1, so changed it as I only collect one of each KM#, so it was an obvious error on my part.
My question is below.
Can I find out if I have made any other errors of this type easily, or do I have to check every single coin?
I have 356 pages to look through if I have to check individually.

Maybe click the Excel download link, then click Find for 11 in Quantity column.
Or temporarily open up your collection like last time and I can have a look.

The way I find in excel is to use the Ctrl+F function.

I down loaded my collection in excel, then clicked on the arrow in the quantity box, near top right, and the drop down box informed me that I had quantities of 1, 2, etc. I removed ticks from the box on left hand side of number. Clicking on one of the two icons, then displayed only those coins where I had made the quantity problem, of which I had seven.
I made a note of those that were listed, then individually altered the quantity in the main listings.
I now have 14,797 'coins' and 14,797 'different coins'. All happy now.
Thanks for help.