Help Needed: Issue with Compounding Contract Year Salary Increase Values

[jmaurer17]

Hi everyone,

I'm encountering an issue with my DAX measure for calculating the cumulative percentage salary increase over multiple contract years. The measure is not correctly compounding the salary increase values. Here is the DAX code I'm using:

Cumulative % Salary Increase = 
VAR CY1Increase = SELECTEDVALUE('CY 1 Salary Inc'[CY 1 Salary Inc], 0) / 100
VAR CY2Increase = SELECTEDVALUE('CY 2 Salary Inc'[CY 2 Salary Inc], 0) / 100
VAR CY3Increase = SELECTEDVALUE('CY 3 Salary Inc'[CY 3 Salary Inc], 0) / 100

VAR ContractYear = SELECTEDVALUE(SPC[Contract Year], 1)  

RETURN 
SWITCH(
    TRUE(),
    ContractYear = 1, CY1Increase * 100,  
    ContractYear = 2, ((1 + CY1Increase) * (1 + CY2Increase) - 1) * 100,  
    ContractYear >= 3, ((1 + CY1Increase) * (1 + CY2Increase) * (1 + CY3Increase) - 1) * 100,  
    BLANK()
)

The goal is to correctly compound the salary increases for each contract year. However, the results I'm getting don't seem to reflect the expected compounded values.

I suspect there might be a precision point error affecting the calculations. All data types involved in the calculations are set to decimal numbers.

Could someone please help me identify what might be going wrong with this measure? Any insights or suggestions would be greatly appreciated!

Thank you in advance!

[jmaurer17]

Appreciate the response. Here is the input and desired output:

Contract Year Salary Inc input parameter Expected Cumulative % Increase

CY 1 - 2.0%	2.00%
CY 2 - 3.0%	5.06% (2% compounded with 3%)
CY 3 - 3.0%	8.14% (2% → 3% → 3% compounded)

So the user a inputs a contract year salary increase percentage for one or all of the contract years. I get numbers close to this figure, but not exact - leading me to suspect a precision error. 

---

[lbendlin]

So the user a inputs a contract year salary increase percentage for one or all of the contract years

How? How does the user input these numbers?

[jmaurer17]

The user inputs a percent increase into one or all (three) Contract Year Salary Inc parameters. I have a seperate numeric paramater for each contract year CY 1 through CY 3 in this case

[lbendlin]

Don't see the issue?

[lbendlin]

Any particular reason for not using PRODUCTX ?

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