condition mean min max ZT0-3 2.99432800825 2.5877552605 3.4009007560000004 ZT4-7 4.8916604935 4.030900126500001 5.7524208605 ZT8-11 5.544357342 5.2235090584999995 5.8652056255 ZT12-15 4.5675860762500005 4.3133661695 4.821805983 ZT16-19 4.5099467545 3.5380717425 5.4818217664999995 ZT20-23 8.3683021435 7.2483720245 9.488232262499999