How to Use the CORREL Function in Microsoft Excel

1. Start Microsoft Excel. You can do this by clicking on Start, highlighting Programs, and clicking Microsoft Excel, or double-clicking the Microsoft Excel icon on your computer's desktop.
2. Before we work with data, it's important to understand an important fact about the correlation coefficient, the value that represents the strength of the relationship between two random variables. The correlation coefficient ranges from -1 to 1, with -1 indicating a perfect negative correlation and 1 indicating a perfect positive correlation.
3. Enter the data. I'll use cells A1 to A25 and B1 to B25 for this purpose. The A column represents each student's homework average and the B column refers to each student's exam average.
4. Enter the following values, starting with cell A1 and ending with cell A25: 89, 92, 88, 76, 90, 68, 100, 87, 93, 77, 81, 80, 94, 90, 83, 79, 73, 83, 91, 84, 88, 90, 93, 80, 91.
5. Now enter the following values, starting with cell B1 and ending with cell B25: 76, 83, 80, 84, 81, 90, 92, 78, 70, 93, 82, 90, 98, 75, 67, 72, 90, 82, 77, 81, 87, 63, 92, 71, 82.
6. Now we can calculate the correlation coefficient. In cell A27, type =CORREL(A1:A25, B1:B25). A1 to A25 and B1 to B25 is where the data appears. Hit ENTER.
7. The result is -.07965, indicating a very slight weak relationship between the two variables.