__Percent Change__This tool enables you to calculate the percentage change between two values like the increase of a rent or of a production.

**CALCULATOR**

Second value:

Our percent calculator uses this formula:

((y2 - y1) / y1)*100 = your percentage change

(where y1=first value and y2=second value)

__Calculate the percentage increase of the rent__Your rent has just increased. It rose from USD 789 to USD 807.46, an increase of just under USD 20. What is the increase in percentage?

(807,46 − 789) / 789 × 100 = 18.46 ÷ 789 × 100 = 2,339

Your rent has increased by 2.34%. We can verify that: 789 × 1,0234 = 807,46

__Calculate the production decline in percentage__The production of a company diminishes from 2,345 pieces per day to 1,870 pieces per day. What is the percentage decrease in production of this company?

(1 870 − 2 345) / 2 345 × 100 = −20.256

The decrease in production is equal to -20.26%. We can verify that: 2,345 × (1 - 20,26 ÷ 100) = 2,345 × 0,7974 = 1,870 rounded to the nearest unit.

__How to determine the percentage of a reduction__A seller gives you a discount of 30 € on a household electrical appliance to 210 €. What is the percentage reduction? You will pay 180 € instead of the 210 € requested. The tool gives us:

(180 − 210) ÷ 210 × 100 = −14,29. The change from 210 to 180, in percentage, represents a decrease of -14.29% of 210.

__Calculate the evolution in percentage of negative values__In order to calculate the change in percentage on negative values, one must take the absolute value of the initial value:

(new-old) / |old|.

A temperature drops from -20 degrees Celcius to -45 degrees Celcius. What is the percent change?

(-45 – (-20)) / 20 * 100 = 125

The temperature has dropped by 125%.

We can verify: 125% of 20 degrees Celcius represents 25 degrees Celcius. This gives -20 – 25 = -45 degrees.