The Date Function in Excel

There are a numbers of different reasons why you would want a Date or Time function in a spreadsheet: If you're running your own company, you might want to record when an order was received and when it was processed. You could then calculate the difference between the two, so that you check how fast the orders were being processed. We'll do that now.

The Excel Date Function

As an example of how to use date functions in Excel, we'll contruct as simple spreadsheets for an order form. We'll enter the date an order was taken, the date the order was sent, and how long it took to be processed. So, to make a start, create the spreadsheet below :

A Simple Excel 2007 Order Form

Click inside cell A2, and we'll enter a date. To enter a date, Click on the Formulas menu at the top of Excel. Then locate the Function Library panel. From the Function Library panel, click on Date & Time:

The Date and Time panel in Excel 2007

As you can see, there's quite a lot of Date and Time functions! Click on Date from the menu, and you'll get the following dialogue box:

The Function Arguments dialogue box

You're now being asked enter a full date.

  • In the Year box, enter 2016
  • In the Month box, enter the number 4
  • In the Day box, enter the number 15
  • Click the OK button
  • Excel will enter the Date in your selected cell, A2 for us

A date entered in an Excel Cell

Notice the DATE Function in the Formula bar:

=DATE(2016, 4, 15)

Between the round brackets of DATE, the Year comes first, then the Month, then the Day.

If you want to format your date as say Monday 15th of April, then you need to click on the Home tab from the Ribbon at the top of Excel. Locate the Nmumber panel, and you'll see Date already displayed:

The Date option in the Number panel in Excel 2007

Click the down arrow to see more options:

Long Date in Excel 2007

Click the Long Date item. Or click on More at the bottom to see some more Date formats to choose from. Your spreadsheet will then look like this:

A Date entered into cell A2 of an Excel spreadsheet

In cell B2, under your Date Order Sent heading, enter another Date Function. This time, have the date read May 3, 2016:

Another date entered

In cell C2, under Time Taken, we'll work out how many days the order took to be sent out.

The Days360 Function in Excel

When you want to work out how many days there are between two dates, the function to use is Days360( ). We want to work out how many days there are between the 15th of April 2016 and the 3rd of May 2016. So click inside cell C2 and do the following:

Click on the Formulas tab at the top of Excel. Then locate the Function Library panel. From the Function Library panel, click on Date & Time. From the menu, click on Days360(). You should see the Function Arguments dialogue box appear again. This time, it will look like this:

Days360 in Excel

The Days360 function needs a start date and an end date. You can enter your cell references here. So in the Start_date box, enter A2. In the End_Date box, enter B2. If you enter the word True in the Method box, Excel will calculate using the European date system. Click OK, to return to your spreadsheet and you might see this:

The wrong cell format

(If your C2 cell has a lot of #### symbols in it, it means that your column is not wide enough. Widen the C column and they'll go away!)

The answer we got was January 18th 1900! The reason for such a bizarre answer is that we've formatted the C2 cell as a date. But the answer to the Days360 function is not a date - it's a number. If you have the same strange answer, then format your C2 as a number. Your spreadsheet will then look like ours below:

Format the cell as a Number

So the difference between the two dates is 18 days.

Entering dates can be fairly straightforward, like cells A2 and B2. But performing calculations with dates can be slightly more complex. To get you some more practise, here's an exercise.


Exercise

Use a Days360 function to work out how many days are left before your next birthday.

Instead of typing out the current date in say cell A2, you can use this inbuilt function:

=Now( )

The Now function doesn't need anything between the round brackets. Once you have today's date, you can enter your birthday in say cell B2.

 

In the next part, we'll take a look at how to handle Time functions in Excel .