condition mean min max ZT0-3 16.150000000000002 16.150000000000002 16.150000000000002 ZT4-7 1.5 1.5 1.5 ZT8-11 3.4000000000000004 3.4000000000000004 3.4000000000000004 ZT12-15 6.35 6.35 6.35 ZT16-19 30.400000000000002 30.400000000000002 30.400000000000002 ZT20-23 25.450000000000003 25.450000000000003 25.450000000000003