condition mean min max ZT0-3 2.9717585 1.9547720000000002 3.988745 ZT4-7 2.7152700000000003 2.7152700000000003 2.7152700000000003 ZT8-11 3.24712 3.24712 3.24712 ZT12-15 0 0 0 ZT16-19 2.67467 2.67467 2.67467 ZT20-23 5.913895 5.913895 5.913895