condition mean min max ZT0-3 9.44313 3.17599 14.672350000000002 ZT4-7 3.3579299999999996 3.3579299999999996 3.3579299999999996 ZT8-11 3.5180949999999998 3.5180949999999998 3.5180949999999998 ZT12-15 7.2497775 5.913035 8.58652 ZT16-19 10.56775 10.56775 10.56775 ZT20-23 16.509349999999998 16.509349999999998 16.509349999999998