condition mean min max ZT0-3 3.5036390264999997 1.346093074 5.661184979 ZT4-7 2.76763887425 2.0955667285 3.43971102 ZT8-11 4.18149076825 3.473967926 4.889013610499999 ZT12-15 5.29258735925 4.8991463815000005 5.686028337 ZT16-19 3.14088451125 2.917595304 3.3641737185 ZT20-23 4.57632633675 4.411047601 4.7416050725000005