condition mean min max ZT0-3 32.93273 32.93273 32.93273 ZT4-7 27.415985499999998 27.415985499999998 27.415985499999998 ZT8-11 17.294109 17.294109 17.294109 ZT12-15 20.6039175 20.6039175 20.6039175 ZT16-19 11.375034 11.375034 11.375034 ZT20-23 11.9162885 11.9162885 11.9162885