condition mean min max ZT0-3 22.350355 22.350355 22.350355 ZT4-7 24.4369705 24.4369705 24.4369705 ZT8-11 24.117014 24.117014 24.117014 ZT12-15 18.728565500000002 18.728565500000002 18.728565500000002 ZT16-19 23.5857365 23.5857365 23.5857365 ZT20-23 27.750722500000002 27.750722500000002 27.750722500000002