condition mean min max ZT0-3 7.429415 2.970295 14.232949999999999 ZT4-7 18.821649999999998 18.821649999999998 18.821649999999998 ZT8-11 35.21595 35.21595 35.21595 ZT12-15 18.257075 11.693449999999999 24.820700000000002 ZT16-19 11.346250000000001 11.346250000000001 11.346250000000001 ZT20-23 5.751519999999999 5.751519999999999 5.751519999999999