SUMX2MY2 in Excel: Difference of Squared Totals Without Confusion

• Introduced: first introduction version is not established by the official history reviewed; the current product list is not a launch record.
• Availability: official help lists Excel for Microsoft 365, Excel for Microsoft 365 for Mac, Excel 2024, Excel 2024 for Mac, Excel 2021, Excel 2021 for Mac, Excel 2019, Excel 2016.
• Checked: October 14, 2026; official SUMX2MY2 reference. Documentation and independently calculated examples; no native Excel execution or broader platform certification.

=SUMX2MY2(array_x, array_y)

Both arrays are required. Microsoft documents #N/A when they contain different numbers of values. Its referenced-input rule ignores text, logical values and empty cells, while numeric zeros participate.

Use equally sized, fully numeric ranges for the examples. The compact ignore rule does not fully explain every mixed-type pairing scenario, so this guide does not infer how blank/text positions should be re-paired or matched across dissimilar shapes.

Enter A2:B4:

In C2 enter =A2^2-B2^2 and fill through C4. Expected contributions are 8,12,-25.

=SUMX2MY2(A2:A4,B2:B4)
=SUM(C2:C4)

Both expected results are -5. A negative answer is valid: the y values have the larger total squared magnitude.

=SUMXMY2(A2:A4,B2:B4)

The expected result is 33, from (3−1)²+(4−2)²+(0−5)²=4+4+25. SUMXMY2 measures squared differences; SUMX2MY2 measures a difference of squared totals.

The names encode different parentheses. For a single pair 3 and 1, x²−y² is eight while (x−y)² is four. A result can be syntactically valid and still answer the wrong question if those operations are confused.

=SUMSQ(A2:A4)-SUMSQ(B2:B4)

Expected result: -5, from 25−30. For these complete numeric arrays, the algebraic identity is a transparent independent control.

This also explains a limitation as an alignment test: reordering the y values does not change their squared total, so SUMX2MY2 can remain unchanged even if row identities have been shuffled. That invariance does not authorize mismatched lengths or resolve the vendor’s mixed-type pairing rules.

=SUMX2MY2(B2:B4,A2:A4)

Expected result: 5. Reversing the arrays reverses the sign because 30−25 is the opposite difference.

Negating every x value while retaining y instead leaves the original expected result at -5, since (-x)²=x². The same is true if all y values are negated. This function cannot reveal the signs of individual original measurements from their squared contributions.

Create D2:E3 with x values 3,4 and y values 0,5:

=SUMX2MY2(D2:D3,E2:E3)

Expected result: 0, because both squared totals are 25. Yet the paired observations differ, and =SUMXMY2(D2:D3,E2:E3) gives 10.

A zero difference of squared totals is therefore not a proof of agreement between two datasets. Use the statistic that matches the comparison you actually need.

Doubling every value in both original arrays multiplies the expected result by four, giving -20. Squared quantities scale with the square of a common multiplier.

Adding ten to both arrays instead gives x values 13,14,10 and y values 11,12,15. Their squared totals are 465 and 490, so the new difference is -25. A common additive shift does not generally preserve this function’s result, unlike a sum of squared pairwise differences.

Keep units and origin choices explicit. Comparing squared quantities from incompatible units has no ordinary interpretation merely because the formula returns a number.

The arrays A2:A4 and B2:B3 have different numeric lengths and violate Microsoft’s rule, with documented expected #N/A. No exact code is guessed for every malformed reference, error-containing range or imported type.

For a sum rather than a difference of squared totals, see SUMX2PY2. The finite identities here do not certify native cancellation accuracy when two very large squared totals are nearly equal.

• Microsoft SUMX2MY2 reference.
• Editorial testing standards.

Inputs are fictional. Decimal answers are independent mathematical expectations rounded to nine places, not captured native results. Extreme magnitudes, complete coercion matrices and cross-version numerical accuracy remain untested.