condition mean min max ZT0-3 14.284375 13.44975 15.119 ZT4-7 17.013550000000002 17.013550000000002 17.013550000000002 ZT8-11 20.16485 20.16485 20.16485 ZT12-15 0 0 0 ZT16-19 20.8566 20.8566 20.8566 ZT20-23 20.914 20.914 20.914