The Fisher Transformation is frequently used to test hypotheses on the correlation coefficient.
The formula for the Fisher Transformation is:
and the Inverse Fisher Transformation is given by the formula:
The inverse Fisher transformation function is shown in the graph below:
See the Wikipedia Fisher Transformation page for further details.The Excel Fisherinv function calculates the inverse of the Fisher Transformation and returns a value between 1 and +1.
The syntax of the function is:
Where y is the value for which you want to calculate the inverse of the Fisher Transformation.
In the spreadsheet below, the Excel Fisherinv Function is used to calculate the inverse of the Fisher Transformation for 3 different values.
Formulas:
 Results:

For further details and examples of the Excel Fisherinv function, see the Microsoft Office website.
If you get an error from the Excel Fisherinv function, this is likely to be the #VALUE! error:
#VALUE!    Occurs if the supplied value of y is nonnumeric. 