condition mean min max ZT0-3 63.2424883925 52.454509085 74.0304677 ZT4-7 20.628879145 18.44894048 22.80881781 ZT8-11 16.9852418475 14.27025707 19.700226625 ZT12-15 20.751327812499998 19.666616249999997 21.836039375 ZT16-19 34.285009195 30.89082333 37.67919506 ZT20-23 56.6024569575 52.695963855 60.508950060000004