condition mean min max ZT0-3 5.45 5.45 5.45 ZT4-7 2.4 2.4 2.4 ZT8-11 4.800000000000001 4.800000000000001 4.800000000000001 ZT12-15 8.75 8.75 8.75 ZT16-19 5.6 5.6 5.6 ZT20-23 3.7 3.7 3.7