condition mean min max ZT0-3 5.503021666666666 1.53379 7.496205 ZT4-7 1.7550000000000001 1.7550000000000001 1.7550000000000001 ZT8-11 2.002665 2.002665 2.002665 ZT12-15 3.6492250000000004 2.476245 4.822205 ZT16-19 5.45032 5.45032 5.45032 ZT20-23 8.485199999999999 8.485199999999999 8.485199999999999