condition mean min max ZT0-3 1.7801375 1.4954450000000001 2.0648299999999997 ZT4-7 3.17562 3.17562 3.17562 ZT8-11 5.29505 5.29505 5.29505 ZT12-15 0 0 0 ZT16-19 7.04496 7.04496 7.04496 ZT20-23 4.371665 4.371665 4.371665