condition mean min max ZT0-3 6.2326250000000005 6.2326250000000005 6.2326250000000005 ZT4-7 5.008065 5.008065 5.008065 ZT8-11 4.8833400000000005 4.8833400000000005 4.8833400000000005 ZT12-15 5.554095 5.554095 5.554095 ZT16-19 6.970435 6.970435 6.970435 ZT20-23 6.91999 6.91999 6.91999