One very ‘in-demand’ type of calculation in Excel is date arithmetic, which is often an integral part of invoicing or budgeting. You want to display dates that will occur after a given time period in relation to another given date. For example, you might seek to answer a question such as: what will the date be three months from now? And rather than having to manually enter or update the date in question each time, have this calculation built in your spreadsheet via a formula. Here’s how:
Excel’s TODAY function is a simple way of taking today’s date from your computer’s clock and displaying it in a cell in your spreadsheet. All you need to do is type =TODAY() as follows into a cell and press Enter to see the result:
=TODAY()
However, the key consideration is that Excel treats all date/time values as numbers, for all calculation purposes, which can complicate your attempt to add another amount to an existing date. For example, if you want to add 3 months on today’s date, you need to be aware that in Excel, the basic unit of a date value is an individual day; which means that, simply adding the number 3 on to today’s date will display the date 3 days from now. Which would be just fine, if that be your intention. However, to be able to choose which date/time interval to use in your calculation, you need to incorporate other Excel date functions.
You can use functions such as YEAR, MONTH and DAY to break a date value down to its constituent components, and then add your chosen value to the appropriate component. You can then use another of Excel’s date/time functions, the DATE function, to compile these individual components (year, month and day) into the desired date result. Let’s consider the example below, assuming that cell B3 contains the current date and the adjacent cell C3 contains a number of years. The YEAR function will extract the year from B3 as a separate individual value, and you can then add the required number of years on to this value specifically. In the result cell, you can then incorporate the YEAR function along with the DAY and MONTH function as parts within the DATE function to calculate the desired result, as seen below:
In this way, you can manipulate date values in Excel to produce the desired type of elapsed time measurements, and this method should produce this result:
Not as simple and intuitive as it might be, but it works!