# Order of Operations

When the programmers developed Excel to do math for us, they programmed Excel to *always* perform the math using very strict order of operations. Excel will *always* calculate anything in **P**arenthesis ( ) first. Always. Then it will calculate any **E**xponents (^). Then, from left to right, Excel will calculate **M**ultiplication (*) and **D**ivision (/). And last, Excel will calculate, again from left to right, **A**ddition (+) and **S**ubtraction (-).

That’s the ‘trick’ to getting those Facebook Memes about solving math problems correctly. (see left)

PEMDAS is a mathematical acronym that reminds us of the order of operations used with complex calculations. Understanding this order is critical if you’re going to use more than one type of calculation in your formula.

In the examples below, Excel will come up with very different results if you neglect the Order of Operations.

Reading left to right, you create the equation this way, subtracting the**Birth Date**from the

**Retirement Date**, and then dividing by

**365.25**(the number of days in a year). You’d get the correct result if you subtracted, and

*then*you divided. But that’s not what you told Excel to do.

In the example above, you neglected to communicate with Excel to subtract the **Birth Date** from the **Retirement Date ***First *(by using parenthesis). So Excel did the division first (**Retirement Date** divided by **365.25** ), and then subtracted that result from the **Birth Date**, resulting in the very wrong result.

The correct Order of Operations is below:

## How to remember the correct Order of Operations?

I re-teach PEMDAS every time I teach Excel. I teach it in a basic essentials class and I teach it for the advanced class. It’s that important. When you’re creating your Formulas and/or Functions in Excel, if you neglect to communicate with Excel the order in which you want the calculation preformed, then Excel is going to *always* default back and use mathematical Order of Operations.

Learn more about absolute vs relative references and grouping dates in PivotTables, or Contact us directly and ask about personalized training in Excel. .