condition mean min max ZT0-3 14.197191 14.197191 14.197191 ZT4-7 14.382431 14.382431 14.382431 ZT8-11 12.682556 12.682556 12.682556 ZT12-15 11.9451255 11.9451255 11.9451255 ZT16-19 12.8003765 12.8003765 12.8003765 ZT20-23 13.204336000000001 13.204336000000001 13.204336000000001