condition mean min max ZT0-3 1.6922175000000002 1.42226 1.9621750000000002 ZT4-7 2.477405 2.477405 2.477405 ZT8-11 1.942915 1.942915 1.942915 ZT12-15 0 0 0 ZT16-19 2.494335 2.494335 2.494335 ZT20-23 2.609125 2.609125 2.609125