condition mean min max ZT0-3 6.1903602087500005 5.2319181310000005 7.1488022865000005 ZT4-7 5.2233514862499995 4.9674890105 5.479213961999999 ZT8-11 8.12925731525 6.7832956805 9.475218949999999 ZT12-15 11.07910720025 9.2037916005 12.9544228 ZT16-19 14.635450760000001 14.043962485000002 15.226939035000001 ZT20-23 18.171436857499998 16.423557965 19.91931575