condition mean min max ZT0-3 9.4452889955 9.323734267999999 9.566843723 ZT4-7 7.73788193875 7.344959981500001 8.130803896 ZT8-11 7.6406011255 6.9387821800000005 8.342420071 ZT12-15 12.8448390525 11.869251705 13.8204264 ZT16-19 20.3665746725 17.624424615000002 23.10872473 ZT20-23 26.3808993 25.89625135 26.86554725