condition mean min max ZT0-3 1.741104801 1.339680954 2.142528648 ZT4-7 3.6264280755 2.646362252 4.606493899 ZT8-11 3.981836118 3.8978823955 4.0657898405 ZT12-15 3.5571023395 2.7206645455 4.3935401335 ZT16-19 6.331393454500001 4.9844323059999995 7.678354603000001 ZT20-23 8.62723395725 8.5492042685 8.705263646