condition mean min max ZT0-3 11.389583 11.389583 11.389583 ZT4-7 14.034574 14.034574 14.034574 ZT8-11 16.1935055 16.1935055 16.1935055 ZT12-15 16.096199 16.096199 16.096199 ZT16-19 14.88393 14.88393 14.88393 ZT20-23 15.25186 15.25186 15.25186