condition mean min max ZT0-3 2.4101250000000003 1.483485 3.4941500000000003 ZT4-7 1.580015 1.580015 1.580015 ZT8-11 3.48568 3.48568 3.48568 ZT12-15 4.4822775 3.70122 5.263335 ZT16-19 4.03182 4.03182 4.03182 ZT20-23 4.1183950000000005 4.1183950000000005 4.1183950000000005