condition mean min max ZT0-3 3.4312 3.4312 3.4312 ZT4-7 2.18268 2.18268 2.18268 ZT8-11 2.23069 2.23069 2.23069 ZT12-15 3.48168 3.48168 3.48168 ZT16-19 4.22039 4.22039 4.22039 ZT20-23 3.488775 3.488775 3.488775