condition mean min max ZT0-3 1.9997475 0.4099275 3.248755 ZT4-7 0.7934345 0.7934345 0.7934345 ZT8-11 0.6679269999999999 0.6679269999999999 0.6679269999999999 ZT12-15 1.0823285 1.0366715 1.1279855 ZT16-19 1.1273 1.1273 1.1273 ZT20-23 3.17999 3.17999 3.17999