condition mean min max ZT0-3 6.6522825 6.36328 6.941285000000001 ZT4-7 5.908105000000001 5.908105000000001 5.908105000000001 ZT8-11 4.0039750000000005 4.0039750000000005 4.0039750000000005 ZT12-15 0 0 0 ZT16-19 6.20298 6.20298 6.20298 ZT20-23 7.446275 7.446275 7.446275