condition mean min max ZT0-3 10.783431666666667 5.887969999999999 16.44825 ZT4-7 12.617799999999999 12.617799999999999 12.617799999999999 ZT8-11 13.67375 13.67375 13.67375 ZT12-15 8.9124425 5.299885 12.524999999999999 ZT16-19 20.28125 20.28125 20.28125 ZT20-23 14.99755 14.99755 14.99755