You can use the following basic formulas to apply a percentage increase or percentage decrease to values in Excel:

**Method 1: Apply Percentage Increase**

=A1*(1+B1)

**Method 2: Apply Percentage Decrease**

=A1*(1-B1)

In both formulas, cell **A1** contains the original value and cell **B1** is the percentage that we’re increasing or decreasing the original value by.

The following examples show how to use each formula in practice.

**Example 1: Apply Percentage Increase to Values**

Suppose we have the following list of values in Excel:

We can use the following formula in cell **C2** to apply a 25% increase to the value in cell **A2**:

=A2*(1+B2)

The following screenshot shows how to use this formula in practice:

Each value in column A has been increased by 25%.

For example:

**10**has been increased by 25% to**12.5**.**15**has been increased by 25% to**18.75**.**18**has been increased by 25% to**22.5**.**20**has been increased by 25% to**25**.

And so on.

**Example 2: Apply Percentage Decrease to Values**

Once again suppose we have the following list of values in Excel:

We can use the following formula in cell **C2** to apply a 10% decrease to the value in cell **A2**:

=A2*(1-B2)

The following screenshot shows how to use this formula in practice:

Each value in column A has been decreased by 10%.

For example:

**10**has been decreased by 10% to**9**.**15**has been decreased by 10% to**13.5**.**18**has been decreased by 10% to**16.2**.**20**has been decreased by 10% to**18**.

And so on.

**Additional Resources**

The following tutorials explain how to perform other common tasks in Excel:

How to Find the Top 10% of Values in an Excel Column

How to Calculate Cumulative Percentage in Excel

How to Multiply Column by a Percentage in Excel