condition mean min max ZT0-3 15.733524999999998 14.418949999999999 17.048099999999998 ZT4-7 14.998750000000001 14.998750000000001 14.998750000000001 ZT8-11 18.104950000000002 18.104950000000002 18.104950000000002 ZT12-15 0 0 0 ZT16-19 18.971049999999998 18.971049999999998 18.971049999999998 ZT20-23 23.47635 23.47635 23.47635