condition mean min max ZT0-3 175.67464045 122.5749142 228.7743667 ZT4-7 302.4148254 299.57843065 305.25122015 ZT8-11 211.8517936625 159.679520625 264.0240667 ZT12-15 32.7713713175 19.302204970000002 46.240537665 ZT16-19 27.36505978 23.785690334999998 30.944429225 ZT20-23 20.4777377675 19.233986955 21.72148858