condition mean min max ZT0-3 0.223334 0.223334 0.223334 ZT4-7 0.66186 0.66186 0.66186 ZT8-11 1.10683 1.10683 1.10683 ZT12-15 0.9414864999999999 0.9414864999999999 0.9414864999999999 ZT16-19 0.857307 0.857307 0.857307 ZT20-23 0.650515 0.650515 0.650515