condition mean min max ZT0-3 5.0627699999999995 4.6520399999999995 5.4735 ZT4-7 8.61311 8.61311 8.61311 ZT8-11 4.213935 4.213935 4.213935 ZT12-15 0 0 0 ZT16-19 5.69692 5.69692 5.69692 ZT20-23 7.40444 7.40444 7.40444