condition mean min max ZT0-3 10.788765 6.043095 13.8829 ZT4-7 2.9058 2.9058 2.9058 ZT8-11 4.03298 4.03298 4.03298 ZT12-15 8.3511875 7.444795 9.25758 ZT16-19 8.86811 8.86811 8.86811 ZT20-23 14.142800000000001 14.142800000000001 14.142800000000001