condition mean min max ZT0-3 24.150000000000002 24.150000000000002 24.150000000000002 ZT4-7 2.1 2.1 2.1 ZT8-11 31.8 31.8 31.8 ZT12-15 12.950000000000001 12.950000000000001 12.950000000000001 ZT16-19 3.75 3.75 3.75 ZT20-23 38.150000000000006 38.150000000000006 38.150000000000006