condition mean min max ZT0-3 3.8000000000000003 3.8000000000000003 3.8000000000000003 ZT4-7 2.4 2.4 2.4 ZT8-11 6.05 6.05 6.05 ZT12-15 2.4 2.4 2.4 ZT16-19 2.1500000000000004 2.1500000000000004 2.1500000000000004 ZT20-23 3.3499999999999996 3.3499999999999996 3.3499999999999996