condition mean min max ZT0-3 6.30830432575 5.6274512255 6.989157426 ZT4-7 4.191772197000001 3.8624887450000003 4.521055649 ZT8-11 5.83061911475 5.1450461635 6.516192066 ZT12-15 4.20982289925 3.284350115 5.1352956835 ZT16-19 3.39983778375 2.6182164685 4.181459099 ZT20-23 6.871895286499999 5.7893819314999995 7.9544086415