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Value  =  Price × Quantity      or Nominal GDP  =  GDP Deflator × Real GDP

Let’s look at an example at the micro level. Suppose the t-shirt company, Coolshirts, sells 10 t-shirts at a price of $9 each.

Coolshirt's nominal revenue from sales  =  Price × Quantity  =  $9 × 10  =  $90


Coolshirt's real income  =  Nominal revenue Price  =  $90 $9  =  10

In other words, when we compute “real” measurements we are trying to get at actual quantities, in this case, 10 t-shirts.

With GDP, it is just a tiny bit more complicated. We start with the same formula as above:

Real GDP  =  Nominal GDP Price Index

For reasons that will be explained in more detail below, mathematically, a price index is a two-digit decimal number like 1.00 or 0.85 or 1.25. Because some people have trouble working with decimals, when the price index is published, it has traditionally been multiplied by 100 to get integer numbers like 100, 85, or 125. What this means is that when we “deflate” nominal figures to get real figures (by dividing the nominal by the price index). We also need to remember to divide the published price index by 100 to make the math work. So the formula becomes:

Real GDP  =  Nominal GDP Price Index / 100

Now read the following Work It Out feature for more practice calculating real GDP.

Computing gdp

It is possible to use the data in [link] to compute real GDP.

Step 1. Look at [link] , to see that, in 1960, nominal GDP was $543.3 billion and the price index (GDP deflator) was 19.0.

Step 2. To calculate the real GDP in 1960, use the formula:

Real GDP  =  Nominal GDP Price Index / 100  =  $543.3 billion 19 / 100  =  $2,859.5 billion

We’ll do this in two parts to make it clear. First adjust the price index: 19 divided by 100 = 0.19. Then divide into nominal GDP: $543.3 billion / 0.19 = $2,859.5 billion.

Step 3. Use the same formula to calculate the real GDP in 1965.

Real GDP  =  Nominal GDP Price Index / 100  =  $743.7 billion 20.3 / 100  =  $3,663.5 billion

Step 4. Continue using this formula to calculate all of the real GDP values from 1960 through 2010. The calculations and the results are shown in [link] .

(Source: Bureau of Economic Analysis, www.bea.gov)
Converting nominal to real gdp
Year Nominal GDP (billions of dollars) GDP Deflator (2005 = 100) Calculations Real GDP (billions of 2005 dollars)
1960 543.3 19.0   543.3 / (19.0/100) 2859.5
1965 743.7 20.3   743.7 / (20.3/100) 3663.5
1970 1075.9 24.8 1,075.9 / (24.8/100) 4338.3
1975 1688.9 34.1 1,688.9 / (34.1/100) 4952.8
1980 2862.5 48.3 2,862.5 / (48.3/100) 5926.5
1985 4346.7 62.3 4,346.7 / (62.3/100) 6977.0
1990 5979.6 72.7 5,979.6 / (72.7/100) 8225.0
1995 7664.0 82.0  7,664 / (82.0/100) 9346.3
2000 10289.7 89.0 10,289.7 / (89.0/100) 11561.5
2005 13095.4 100.0 13,095.4 / (100.0/100) 13095.4
2010 14958.3 110.0 14,958.3 / (110.0/100) 13598.5

There are a couple things to notice here. Whenever you compute a real statistic, one year (or period) plays a special role. It is called the base year (or base period). The base year is the year whose prices are used to compute the real statistic. When we calculate real GDP, for example, we take the quantities of goods and services produced in each year (for example, 1960 or 1973) and multiply them by their prices in the base year (in this case, 2005), so we get a measure of GDP that uses prices that do not change from year to year. That is why real GDP is labeled “Constant Dollars” or “2005 Dollars,” which means that real GDP is constructed using prices that existed in 2005. The formula used is:

GDP deflator  =  Nominal GDP Real GDP  × 100

Rearranging the formula and using the data from 2005:

Real GDP  =  Nominal GDP Price Index / 100  =  $13,095.4 billion 100 / 100  =  $13,095.4 billion

Comparing real GDP and nominal GDP for 2005, you see they are the same. This is no accident. It is because 2005 has been chosen as the “base year” in this example. Since the price index in the base year always has a value of 100 (by definition), nominal and real GDP are always the same in the base year.

Look at the data for 2010.

Real GDP  =  Nominal GDP Price Index / 100  =  $14,958.3 billion 110 / 100  =  $13,598.5 billion

Use this data to make another observation: As long as inflation is positive, meaning prices increase on average from year to year, real GDP should be less than nominal GDP in any year after the base year. The reason for this should be clear: The value of nominal GDP is “inflated” by inflation. Similarly, as long as inflation is positive, real GDP should be greater than nominal GDP in any year before the base year.

Questions & Answers

Explain the differences between aggregate demand shocks and aggregate supply shocks
Swagger Reply
what are the measures being taken to reduce inflation in LDCs
Athumam Reply
increase level of production,reduce rates of tax charged
What is economic growth!
Doris Reply
Microeconomics can simply be refers to as the study of a unit economy while macroeconomics can be regarded as a study of economy as a whole or aggregate economy of a country.
Hamzat Reply
Full employment price stability economic growth
using geometry, discuss the four interrelated flows in the circular flows of income
Ahmed Reply
who is there?
Demand refers to the quantity of a commodity that one can buy supported by the willingness and the ability to buy
Noor Reply
Which of the following are assets of the Federal Reserve? a. Treasury bills held by the Federal Reserve b. cash in circulation c. Loans made by commercial banks d. the reserves of commercial banks at the Federal Reserve
Julya Reply
what are the four functions served by money
Michele Reply
It serves as a medium of exchange
It serves as a store of value
It serves as a unit of account
It also serves as a standard for Differed Payment.
Acts as a measure of value.
Hey, I am a new member.
Store of value
Hello i want your help if there is someone online
how are you doing
what is balance of payment deficit
A nation or region, which is deficit in exports, and Imports more goods and services and for the payment for imports, it must be borrowed from other states or Nations. mostly, between countries.
Pls Wat ar D Factors to Consedered To Saving
Hello guys how are you doing
I will say a balance of payment deficit is when a country import more goods,services and capital than it export.The country most borrowed from other countries to pay for it imports.
can anyone tell me that why in the income and consumption curve the income is on x axis?
bechar Reply
why inflation in double digit is not good for economy
Obaid Reply
what is mean by zero inflation
some time it is good but some time it is not...
the condition of that economy tell you. is it good are bad?
the definition of the law of demand
Aley Reply
law of damand states all else remains constant or what we can say is ceteris peribus,quantity demanded for a commodity extends with fall in price and vice versa. law of demand explains inverse relationship between price and qua ntity demanded
What is demand and supply
Antwi Reply
Demand refers to how much of that product, item, commodity, or service consumers are willing and able to purchase at a particular price. In other words, supply refers to how much the producers of a product or service are willing to produce and can provide to the market with limited amount of resou
Hello dear
what is gdp per capital and why it is used for?
Era Reply
gross domestic product
gdp per capita is the gross domestic product per person (GDP/population) and is a better indicator of economic health and living standards than GDP alone.
thank you so much 😘
please explain shift in production possibility curve
advances in technology can cause a shift in the ppf because output can increase with use of the same amount of resources (laborers can produce more efficiently, and suppliers are willing to sell more)
but equally natural shocks ie earthquakes or war can move the ppf inward so reducing production capicity
what is crowding out effect?
Sera Reply

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