condition mean min max ZT0-3 4.611493333333334 2.622045 5.855315 ZT4-7 3.241915 3.241915 3.241915 ZT8-11 5.88921 5.88921 5.88921 ZT12-15 10.9481025 9.640455 12.255749999999999 ZT16-19 7.764395 7.764395 7.764395 ZT20-23 9.11948 9.11948 9.11948