condition mean min max ZT0-3 4.4598625 3.9648000000000003 4.954925 ZT4-7 6.10779 6.10779 6.10779 ZT8-11 7.24577 7.24577 7.24577 ZT12-15 0 0 0 ZT16-19 8.957564999999999 8.957564999999999 8.957564999999999 ZT20-23 7.30517 7.30517 7.30517