condition mean min max ZT0-3 3.4829350000000003 3.4829350000000003 3.4829350000000003 ZT4-7 1.6775000000000002 1.6775000000000002 1.6775000000000002 ZT8-11 2.07253 2.07253 2.07253 ZT12-15 2.9111849999999997 2.9111849999999997 2.9111849999999997 ZT16-19 5.56112 5.56112 5.56112 ZT20-23 4.043475 4.043475 4.043475