condition mean min max ZT0-3 22.47775 22.47775 22.47775 ZT4-7 19.37025 19.37025 19.37025 ZT8-11 16.436799999999998 16.436799999999998 16.436799999999998 ZT12-15 16.67085 16.67085 16.67085 ZT16-19 24.4657 24.4657 24.4657 ZT20-23 23.82695 23.82695 23.82695