The statistical functions all follow the same format (syntax) as the SUM function, but with a different function word. For example =SUM(A1:A20) and =AVERAGE(A1:A20). When you are familiar with the syntax these functions can be entered manually on the Formula bar quite quickly.
To create a statistical formula
- Position the active cell where the result is to be displayed
- On the Standard toolbar, click Paste Function
The Paste Function dialogue box is displayed.

Paste Function dialogue box - Statistical functions list
- From the Function category: list, select Statistical
- From the Function name: list, select the function to use
The Function dialogue box is extended to display the function arguments.
- Enter the function arguments and click OK or the green Tick button
or press Enter to accept the formula
Useful functions

There are a range of functions and date calculations available in Excel. Some will present no problems at all, while others may cause potential Year 2000 problems. Remember that you should always type in 4-digit year values and set up your system so that dates are displayed with 4 digits for the year.
For example, both the =Today() and =Now() functions pick up the formatting of the underlying cell, so provided this has been formatted using a 4-digit year the result displayed in the cell will be formatted as a 4-digit date.