condition mean min max ZT0-3 1.8566243704999998 1.8060946919999998 1.9071540489999999 ZT4-7 1.22881794725 1.1368669705 1.3207689239999998 ZT8-11 6.6435733822500005 2.0894441365 11.197702628 ZT12-15 9.806510477 7.742909469000001 11.870111484999999 ZT16-19 4.324201088000001 3.8010892480000003 4.847312928 ZT20-23 4.25339765225 3.8718478285 4.634947476000001