condition mean min max ZT0-3 3.58088 2.890785 4.94116 ZT4-7 6.785495 6.785495 6.785495 ZT8-11 16.0963 16.0963 16.0963 ZT12-15 16.72045 15.617 17.8239 ZT16-19 11.49555 11.49555 11.49555 ZT20-23 6.478805 6.478805 6.478805