Inconsistent precision of displayed values

[devnull-octovon]

Why do values with one decimal-place precision not appear correctly when the last digit is "0"? For example, why are these three consecutive values shown as:

- 67.9
- 68   <- this should appear as 68.0
- 68.1

In the image below, the values circled in green are displayed correctly, but those circled in red do not display the appropriate last digit when it is "0".