condition mean min max ZT0-3 35.3357 35.3357 35.3357 ZT4-7 26.50155 26.50155 26.50155 ZT8-11 11.216854999999999 11.216854999999999 11.216854999999999 ZT12-15 7.807354999999999 7.807354999999999 7.807354999999999 ZT16-19 17.3676 17.3676 17.3676 ZT20-23 34.70655 34.70655 34.70655