condition mean min max ZT0-3 13.521 12.25905 14.6646 ZT4-7 11.688400000000001 11.688400000000001 11.688400000000001 ZT8-11 12.222000000000001 12.222000000000001 12.222000000000001 ZT12-15 24.972225 23.429850000000002 26.5146 ZT16-19 18.3795 18.3795 18.3795 ZT20-23 16.7515 16.7515 16.7515