condition mean min max ZT0-3 4.36401 4.36401 4.36401 ZT4-7 3.4543150000000002 3.4543150000000002 3.4543150000000002 ZT8-11 4.879455 4.879455 4.879455 ZT12-15 5.445265 5.445265 5.445265 ZT16-19 6.13718 6.13718 6.13718 ZT20-23 4.920915 4.920915 4.920915