Nominal and Real GDP If nominal GDP is, for example, \$1,620 billion in 2017 and increases to \$1,680 billion in 2018, is the growth rate 3.7%? Or does real GDP first need to be calculated using a deflator?
As you pointed out, you need to distinguish between real and nominal GDP. The 3.7% growth from 1620 to 1680 is the nominal growth. To figure out real growth, you need to know the price index of the two years.