condition mean min max ZT0-3 3.488127355 3.4820000589999998 3.4942546510000003 ZT4-7 12.478279009000001 9.668375893 15.288182125 ZT8-11 19.10153744 17.55396366 20.64911122 ZT12-15 18.4925022175 18.208188375 18.77681606 ZT16-19 27.6425355025 26.588619344999998 28.69645166 ZT20-23 33.210706134999995 30.86997795 35.55143432