condition mean min max ZT0-3 18.8533105175 14.48368622 23.222934815000002 ZT4-7 29.746577825 26.98951099 32.50364466 ZT8-11 29.62386277 27.172255385 32.075470155 ZT12-15 32.494667282500004 27.76621403 37.223120535 ZT16-19 68.77820040499999 68.67320303 68.88319777999999 ZT20-23 63.107570665000004 62.57116288 63.643978450000006