In Excel 2010, the STDEVP function has been replaced by the STDEV.P function, which has improved accuracy.
The Excel STDEVP function calculates the standard deviation of a supplied set of values.
The syntax of the function is:
where the arguments, number1, [number2], etc, are one or more numeric values, arrays of values, or references to cells containing values.
See the page on Standard Deviation in Excel for a comparison of the different Excel standard deviation functions.
A company keeps a record of its monthly sales figures, over the last three years. These are stored in cells B3-B14, D3-D14 and F3-F14 of the spreadsheet on the right above spreadsheet.
The standard deviation of the three years' sales figures is calculated in cell H3 of the spreadsheet. The formula for this, (shown in the spreadsheet formula bar), is:
As shown in cell H3, the standard deviation for the 3 years of sales figures is calculated to be 2,484.05
In the example above, the arguments to the Stdevp function are input as 3 cell ranges. However, you can also input figures directly, as individual numbers or number arrays.
For example, if, during January and February 2010 the sales figures are 13,000 and 14,500, you could add these directly into the above function as follows:
This gives the updated standard deviation value of 2,435.35
For further information and examples of the Excel Stdevp function, see the Microsoft Office website.
If you get an error from the Excel Stdevp function this is likely to be one of the following:
|#DIV/0!||-||(Note that text representations of numbers, that are supplied as a part of an array, are not recognized as numeric values by the Stdevp function)|
|#VALUE!||-||Occurs if any values that are supplied directly to the Stdevp function are text values that cannot be interpreted as numbers.|