condition mean min max ZT0-3 2.6474125 1.1188225 4.50973 ZT4-7 0.9357265 0.9357265 0.9357265 ZT8-11 3.284815 3.284815 3.284815 ZT12-15 3.5054425 2.852385 4.1585 ZT16-19 1.9404849999999998 1.9404849999999998 1.9404849999999998 ZT20-23 3.274165 3.274165 3.274165