condition mean min max ZT0-3 0.8577648333333333 0.6475865000000001 1.1985105 ZT4-7 0.48947050000000003 0.48947050000000003 0.48947050000000003 ZT8-11 0.5083505 0.5083505 0.5083505 ZT12-15 1.0049345 0.9534739999999999 1.056395 ZT16-19 0.8081895 0.8081895 0.8081895 ZT20-23 0.9562085 0.9562085 0.9562085