condition mean min max ZT0-3 7.933605000000001 5.172040000000001 9.63409 ZT4-7 7.77424 7.77424 7.77424 ZT8-11 16.7052 16.7052 16.7052 ZT12-15 17.064999999999998 14.3582 19.7718 ZT16-19 19.150550000000003 19.150550000000003 19.150550000000003 ZT20-23 12.2228 12.2228 12.2228