condition mean min max ZT0-3 157.246489 157.246489 157.246489 ZT4-7 152.9378335 152.9378335 152.9378335 ZT8-11 170.43334700000003 170.43334700000003 170.43334700000003 ZT12-15 158.242458 158.242458 158.242458 ZT16-19 198.38590299999998 198.38590299999998 198.38590299999998 ZT20-23 180.97953 180.97953 180.97953