condition mean min max ZT0-3 3.08179 2.682485 3.481095 ZT4-7 3.560395 3.560395 3.560395 ZT8-11 6.317715 6.317715 6.317715 ZT12-15 0 0 0 ZT16-19 6.167675 6.167675 6.167675 ZT20-23 4.610495 4.610495 4.610495