condition mean min max ZT0-3 1.333065685 0.7796431620000001 1.886488208 ZT4-7 6.3897061985 3.7622246275 9.0171877695 ZT8-11 14.4664995125 12.82918274 16.103816285 ZT12-15 10.49587286625 9.264085866999999 11.7276598655 ZT16-19 7.964009051750001 7.631051023 8.2969670805 ZT20-23 6.76449163575 6.016928942 7.5120543295