condition mean min max ZT0-3 11.527738 11.527738 11.527738 ZT4-7 13.704427 13.704427 13.704427 ZT8-11 13.220178 13.220178 13.220178 ZT12-15 13.623887 13.623887 13.623887 ZT16-19 15.4545815 15.4545815 15.4545815 ZT20-23 14.4626585 14.4626585 14.4626585