Smart Number % does not match actual decrease


#1

I am using the smart number feature to track performance from week to week. The number showing for this week and last week is accurate but the % difference does not accurately reflect the difference.

This week: 32.1%
Last week: 38.2%
Difference showing: 15.97%
Actual difference: 6.1%

Am I misusing the feature or is this a bug?

48%20AM


#2

Hi @lia
Can you change the format to Table and look at those dates and numbers. Just to verify that the data is correct or not.
It might have something to do with the rolling window, which has an open issue:
https://github.com/metabase/metabase/issues/8977


#3

The difference between your numbers is 16%, it just gets a bit confusing since you already have percentages as your base units.


#4

The problem is that you’re confusing the percent change vs. the percentage points change. This is made confusing because the metric itself that you’re tracking is being expressed as a percentage.

The percentage point change in this case is in fact 6.1 percentage points: 38.2 – 32.1. But the difference between 38.2 and 32.1 is a percentage change of 15.97%. (I.e. 6.1 ÷ 38.2)

For clarity though we might want to consider displaying the percentage point change in this scenario instead of the percent change.