condition mean min max ZT0-3 10.200150550250001 9.3244769005 11.0758242 ZT4-7 1.7274231042500001 1.6611435230000002 1.7937026855 ZT8-11 1.9580319282499998 1.5894931369999998 2.3265707195 ZT12-15 3.20142447525 2.466715112 3.9361338385 ZT16-19 5.5431631525 4.430759973500001 6.655566331499999 ZT20-23 7.7691853605 7.4834034945 8.054967226499999