condition mean min max ZT0-3 108.116923 108.116923 108.116923 ZT4-7 137.947479 137.947479 137.947479 ZT8-11 171.256789 171.256789 171.256789 ZT12-15 143.1983975 143.1983975 143.1983975 ZT16-19 208.2028745 208.2028745 208.2028745 ZT20-23 186.120277 186.120277 186.120277