condition mean min max ZT0-3 3.34466304675 2.8970044275 3.792321666 ZT4-7 4.7079193135 4.5759659479999995 4.839872679 ZT8-11 9.971016692333333 9.224893199333334 10.717140185333333 ZT12-15 7.186673940666667 6.872608166333333 7.500739715000001 ZT16-19 3.558416215 3.132101793 3.9847306369999997 ZT20-23 2.3837316483333337 1.7055934046666668 3.0618698920000003