condition mean min max ZT0-3 2.787675 2.787675 2.787675 ZT4-7 0.50901 0.50901 0.50901 ZT8-11 1.5288955 1.5288955 1.5288955 ZT12-15 5.06556 5.06556 5.06556 ZT16-19 3.124935 3.124935 3.124935 ZT20-23 2.4378599999999997 2.4378599999999997 2.4378599999999997