No of duplicate apps solution in Guided Project 1 not the same result as in Excel pivot table

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My Code:
My code resulted in the same duplicate apps of 1183 for android data

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What I expected to happen:
as per solution, it shows 1181 apps in android that are duplicates app

What actually happened:

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When I check using Excel pivot table, it shows 813 that are duplicated only and 8826 unique apps in android.

I meant my code resulted in the same duplicate apps of 1181 for android data, but was wondering why it shows differently when using Excel pivot table