condition mean min max ZT0-3 10.848567 10.848567 10.848567 ZT4-7 10.3422725 10.3422725 10.3422725 ZT8-11 9.1498965 9.1498965 9.1498965 ZT12-15 14.036000999999999 14.036000999999999 14.036000999999999 ZT16-19 10.0286985 10.0286985 10.0286985 ZT20-23 24.2105315 24.2105315 24.2105315