condition mean min max ZT0-3 2.1668523984999997 2.062989918 2.270714879 ZT4-7 3.4537961957500003 3.0518422000000003 3.8557501915000003 ZT8-11 2.6920379165000003 2.4683905365000003 2.9156852965 ZT12-15 2.2238808480000003 1.8813975635000002 2.5663641325 ZT16-19 2.576034464 2.138860149 3.013208779 ZT20-23 5.6170804819999995 3.6988314215 7.5353295424999995