condition mean min max ZT0-3 3.074695 3.074695 3.074695 ZT4-7 9.499600000000001 9.499600000000001 9.499600000000001 ZT8-11 5.163679999999999 5.163679999999999 5.163679999999999 ZT12-15 4.18957 4.18957 4.18957 ZT16-19 2.8217049999999997 2.8217049999999997 2.8217049999999997 ZT20-23 2.63028 2.63028 2.63028