condition mean min max ZT0-3 2.68426862075 2.224909196 3.1436280455 ZT4-7 5.2168264125 4.176754442 6.256898382999999 ZT8-11 8.236969484 6.8291796005 9.6447593675 ZT12-15 6.3490773955 5.5820032805 7.1161515105 ZT16-19 3.25774829625 3.090350323 3.4251462695 ZT20-23 4.9288891495 4.241402242 5.616376057