I apologize to all of you.
I found the reason, because the system rounded down.
For example: 15.4% ~ 15%, 58.2 ~ 58% and 26.4% ~ 26%.
===> 15.4% + 58.2% + 26.4% = 100%.
However, because the system rounds down: 15% + 58% + 26% = 99%.
I'm sorry to bother you.