Gradient Legend does not Reflect Number Formatting

Here is the conditional color formatting on the visual (stacked column chart type):

Here is the formatting for the 3/12 Sales Growth Measure:

Here is how the legend is actually formatted:

After investigation, I've noticed this pattern:

This is all in a report based on a dataset in the service.

• On percentage-formatted measures from the dataset, the legend formats correctly
• On percentage-formatted measures originating from this report, the legend formats incorrectly