Top 10% Measure Issues

[joshs444444]

I have a DIM item table and a Fact purchse table.

I created a measure to calculate the 2022-2023 purchase spend for each item.

I am trying create another measure that calculates 10% of the 2022-2023 purchase spend.  I want this measure to stay the same for each item, so that it is a static value. I also want it to be recalculated based on the context of the items. So if it is top 10 items, it would be the sum of 10% of the purchase spend for each row, and if it is top 20 items, same thing.

Here is what I have now:

Total Purchases 2022-2023 =

CALCULATE(

    [Total Purchases],

    'Date'[Year] IN {2022, 2023}

)

Top10PercentSpend = CALCULATE( [Total Item Purchase Spend 2022-2023] * 0.1,

ALL('Item')

)

Top10PercentSpend item =

SUMX(

    SUMMARIZE(

        CALCULATETABLE(

            'Purchases',

            VALUES('Item'[Item #])

        ),

        'Item'[Item #],

        "TotalCost", [Total Item Purchase Spend 2022-2023]

    ),

    [Total Item Purchase Spend 2022-2023] * 0.1

)

---
the problem I am running into is getting just the context total. For example, the "Top10PercentSpend" measure is adding up 10% of all purchases no matter the context. However the Top10PercentSpend item measure is calculating the 10% spend for each item individually.

What I really want is the total of the "Top10PercentSpend item" measure in each row.

Any help is appreciated. I am happy to clarify or provide additional context.

Thanks!