condition mean min max ZT0-3 12.181588 12.181588 12.181588 ZT4-7 11.7970355 11.7970355 11.7970355 ZT8-11 11.8937855 11.8937855 11.8937855 ZT12-15 12.415030999999999 12.415030999999999 12.415030999999999 ZT16-19 14.258782 14.258782 14.258782 ZT20-23 12.8635435 12.8635435 12.8635435