condition mean min max ZT0-3 8.489498333333334 7.697979999999999 8.94824 ZT4-7 6.041869999999999 6.041869999999999 6.041869999999999 ZT8-11 4.199365 4.199365 4.199365 ZT12-15 8.1072575 6.42289 9.791625 ZT16-19 6.61871 6.61871 6.61871 ZT20-23 13.18875 13.18875 13.18875