condition mean min max ZT0-3 3.0440969785 2.258594633 3.829599324 ZT4-7 4.49110628225 4.417636215 4.564576349499999 ZT8-11 4.04224935275 3.9739636705 4.110535035 ZT12-15 5.50158983325 5.3375390199999995 5.6656406465 ZT16-19 4.71757832325 4.493369824 4.941786822499999 ZT20-23 3.9515118 3.693908218 4.209115382