condition mean min max ZT0-3 5.8903525000000005 5.32026 6.460445 ZT4-7 3.74124 3.74124 3.74124 ZT8-11 3.93782 3.93782 3.93782 ZT12-15 0 0 0 ZT16-19 5.78639 5.78639 5.78639 ZT20-23 6.823585 6.823585 6.823585