The correlation coefficient is used to determine how related points in a data set are. The coefficient is always in between 0 and 1 (or negative 1 and 0), with 0 being not related and 1 being completely related. So, the closer the coefficient is to 1 (or -1) the stronger the association. Since 0.85 is close to 1 it can be said that the data has a strong linear association.