Have a look at the example in the help section for Partial Correlations. In the example outputs, the mean for the "Required grade" is calculated to be 84.200. However, no datapoint in the "Required Grade" column is greater than 4. It looks like the mean for "required grade" is being calculated using the "general" column, which to me seems WRONG.
What's up with these calculations? The errors with the calculations for the mean lead me to believe that the Partial correlations are being calculated incorrectly also.