condition mean min max ZT0-3 6.400535 6.229945 6.571125 ZT4-7 6.355125 6.355125 6.355125 ZT8-11 7.02977 7.02977 7.02977 ZT12-15 0 0 0 ZT16-19 7.796935 7.796935 7.796935 ZT20-23 6.124890000000001 6.124890000000001 6.124890000000001