condition mean min max ZT0-3 18.044058837500003 16.849441085000002 19.23867659 ZT4-7 15.239446749999999 14.07154687 16.40734663 ZT8-11 21.2434955725 19.588734019999997 22.898257125 ZT12-15 20.1176824525 20.0230521 20.212312805 ZT16-19 20.36133277 19.585183835000002 21.137481705 ZT20-23 18.7106606075 18.278475145 19.142846069999997