condition mean min max ZT0-3 9.524725 9.524725 9.524725 ZT4-7 8.23951 8.23951 8.23951 ZT8-11 8.892 8.892 8.892 ZT12-15 9.46895 9.46895 9.46895 ZT16-19 13.32115 13.32115 13.32115 ZT20-23 14.069600000000001 14.069600000000001 14.069600000000001