condition mean min max ZT0-3 2.595875 2.114915 3.076835 ZT4-7 2.21939 2.21939 2.21939 ZT8-11 4.101375 4.101375 4.101375 ZT12-15 0 0 0 ZT16-19 4.725465 4.725465 4.725465 ZT20-23 4.27502 4.27502 4.27502