Correcting DAX Expression for Accurate Average Spending Calculation

User Concerns Analysis

The user has indicated that the original DAX expression, AvgSpendPerClinic = AVERAGEX(VALUES(Clinics[Location]), SUM(Transactions[Adjusted Gross Sales])), incorrectly calculates the total spending across clinics instead of the average spending per location.

Code Inspection

Upon inspection, the original code utilizes SUM() within an AVERAGEX(), which aggregates total sales for each clinic rather than calculating the average spending per clinic. Consequently, this leads to an inaccurate output for average spending.

Code Rectification

To compute the average spending per clinic correctly, the logic must be adjusted so that the SUM() operation is nested inside the context of each location within the AVERAGEX(). Instead of summarizing before averaging, sales should first be calculated at the clinic level.

Corrected Code

Here is the revised code:

AvgSpendPerClinic = 
AVERAGEX(
    VALUES(Clinics[Location]),
    CALCULATE(SUM(Transactions[Adjusted Gross Sales]))
)

Corrections and Explanations

• Nature of the Issue Corrected: The original formula incorrectly computed total sales values for averaging, leading to misinterpretation as it returned aggregated sales rather than the average per clinic.
• Correction Explanation: By using CALCULATE(SUM(Transactions[Adjusted Gross Sales])), the total adjusted gross sales are computed within the context of each clinic location provided by VALUES(Clinics[Location]). This ensures that for each unique clinic location, the sales are summed correctly before averaging, yielding the accurate average spend per clinic.
• Impact on Functionality and Performance: The corrected formula accurately calculates the average adjusted gross sales per clinic, enhancing the overall integrity of the resultant metric. This not only improves the accuracy of the data insights but also aligns with best practices in DAX calculations by ensuring context switching is handled properly.

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