The degree or the extent of correlation between two variables is described by the value of the correlation coefficients. The degrees of correlation are: Perfect Correlation, Zero Correlation, Limited Degree of Correlation

## Perfect correlation

The perfect correlation exists when two variables change in exactly equal proportion. It is often further classified into two categories.

- Perfect Positive Correlation
- Perfect Negative Correlation

**Perfect positive correlation:Â **When the proportional change in two variables is within the same direction, then it is called a perfect positive correlation. For a perfect positive correlation between two variables, the value of the correlation coefficient is equal to +1.

**Perfect negative correlation:Â **There exists a perfect negative correlation between two variables if the proportional change in the two variables is in the opposite direction. The value of the correlation coefficient for a perfect negative correlation is â€“ 1.

Also, Read Positive and Negative Correlation