condition mean min max ZT0-3 1.3934250000000001 1.3934250000000001 1.3934250000000001 ZT4-7 0.773541 0.773541 0.773541 ZT8-11 1.145971 1.145971 1.145971 ZT12-15 0.744158 0.744158 0.744158 ZT16-19 1.3485395 1.3485395 1.3485395 ZT20-23 1.476415 1.476415 1.476415