condition mean min max ZT0-3 6.27075675 5.7160285 6.8254850000000005 ZT4-7 3.841215 3.841215 3.841215 ZT8-11 6.47053 6.47053 6.47053 ZT12-15 0 0 0 ZT16-19 10.87786 10.87786 10.87786 ZT20-23 7.3759 7.3759 7.3759