condition mean min max ZT0-3 14.138985 14.138985 14.138985 ZT4-7 15.976754 15.976754 15.976754 ZT8-11 14.785024499999999 14.785024499999999 14.785024499999999 ZT12-15 16.7385795 16.7385795 16.7385795 ZT16-19 14.380542 14.380542 14.380542 ZT20-23 13.0995035 13.0995035 13.0995035