condition mean min max ZT0-3 0.761665 0.752765 0.770565 ZT4-7 1.021451 1.021451 1.021451 ZT8-11 0.522925 0.522925 0.522925 ZT12-15 0 0 0 ZT16-19 1.01105 1.01105 1.01105 ZT20-23 0.50594 0.50594 0.50594