condition mean min max ZT0-3 4.3364625 4.3364625 4.3364625 ZT4-7 6.0468625 6.0468625 6.0468625 ZT8-11 5.1966624999999995 5.1966624999999995 5.1966624999999995 ZT12-15 4.5858091666666665 4.5858091666666665 4.5858091666666665 ZT16-19 4.6684675 4.6684675 4.6684675 ZT20-23 3.42358 3.42358 3.42358