This is a problem that has always been happening with all custom UI's because SOE is doing some funky rounding on their end.
When our UI's show you, for example, 69.7%, then we are actually displaying two different numbers for you, namely 69 and 97. This is all that we have from SOE. Now what we do is that we hide the 9 from 97 and display them both as if they were a single number. However, it seems like the 97 is rounded separately from the 69, which is why you see those strange results.
It's all the we can do, though.