condition mean min max ZT0-3 12.166710165 11.89374007 12.43968026 ZT4-7 15.2782215825 12.44257128 18.113871885000002 ZT8-11 21.0313270375 17.772713555 24.289940520000002 ZT12-15 11.22473049325 7.601517103499999 14.847943883000001 ZT16-19 3.7188570505000005 3.602706603 3.8350074980000004 ZT20-23 2.716373539 2.091242458 3.3415046200000003