condition mean min max ZT0-3 9.055928 9.055928 9.055928 ZT4-7 11.0365865 11.0365865 11.0365865 ZT8-11 9.927512 9.927512 9.927512 ZT12-15 9.528633 9.528633 9.528633 ZT16-19 9.321420499999999 9.321420499999999 9.321420499999999 ZT20-23 9.499931 9.499931 9.499931