<< Chapter < Page Chapter >> Page >

Many factors can affect the expected profitability on investment. For example, if the price of energy declines, then investments that use energy as an input will yield higher profits. If government offers special incentives for investment (for example, through the tax code), then investment will look more attractive; conversely, if government removes special investment incentives from the tax code, or increases other business taxes, then investment will look less attractive. As Keynes noted, business investment is the most variable of all the components of aggregate demand.

What determines government spending?

The third component of aggregate demand is spending by federal, state, and local governments. Although the United States is usually thought of as a market economy, government still plays a significant role in the economy. As we discuss in Environmental Protection and Negative Externalities and Positive Externalities and Public Goods , government provides important public services such as national defense, transportation infrastructure, and education.

Keynes recognized that the government budget offered a powerful tool for influencing aggregate demand. Not only could AD be stimulated by more government spending (or reduced by less government spending), but consumption and investment spending could be influenced by lowering or raising tax rates. Indeed, Keynes concluded that during extreme times like deep recessions, only the government had the power and resources to move aggregate demand.

What determines net exports?

Recall that exports    are products produced domestically and sold abroad while imports    are products produced abroad but purchased domestically. Since aggregate demand is defined as spending on domestic goods and services, export expenditures add to AD, while import expenditures subtract from AD.

Two sets of factors can cause shifts in export and import demand: changes in relative growth rates between countries and changes in relative prices between countries. The level of demand for a nation’s exports tends to be most heavily affected by what is happening in the economies of the countries that would be purchasing those exports. For example, if major importers of American-made products like Canada, Japan, and Germany have recessions, exports of U.S. products to those countries are likely to decline. Conversely, the quantity of a nation’s imports is directly affected by the amount of income in the domestic economy: more income will bring a higher level of imports.

Exports and imports can also be affected by relative prices of goods in domestic and international markets. If U.S. goods are relatively cheaper compared with goods made in other places, perhaps because a group of U.S. producers has mastered certain productivity breakthroughs, then U.S. exports are likely to rise. If U.S. goods become relatively more expensive, perhaps because a change in the exchange rate between the U.S. dollar and other currencies has pushed up the price of inputs to production in the United States, then exports from U.S. producers are likely to decline.

[link] summarizes the reasons given here for changes in aggregate demand.

Determinants of aggregate demand
Reasons for a Decrease in Aggregate Demand Reasons for an Increase in Aggregate Demand
  • Rise in taxes
  • Fall in income
  • Rise in interest
  • Desire to save more
  • Decrease in wealth
  • Fall in future expected income
  • Decrease in taxes
  • Increase in income
  • Fall in interest rates
  • Desire to save less
  • Rise in wealth
  • Rise in future expected income
  • Fall in expected rate of return
  • Rise in interest rates
  • Drop in business confidence
  • Rise in expected rate of return
  • Drop in interest rates
  • Rise in business confidence
  • Reduction in government spending
  • Increase in taxes
  • Increase in government spending
  • Decrease in taxes
Net Exports
  • Decrease in foreign demand
  • Relative price increase of U.S. goods
Net Exports
  • Increase in foreign demand
  • Relative price drop of U.S. goods

Key concepts and summary

Aggregate demand is the sum of four components: consumption, investment, government spending, and net exports. Consumption will change for a number of reasons, including movements in income, taxes, expectations about future income, and changes in wealth levels. Investment will change in response to its expected profitability, which in turn is shaped by expectations about future economic growth, the creation of new technologies, the price of key inputs, and tax incentives for investment. Investment will also change when interest rates rise or fall. Government spending and taxes are determined by political considerations. Exports and imports change according to relative growth rates and prices between two economies.


Mahapatra, Lisa. “US Exports To China Have Grown 294% Over The Past Decade.” International Business Times . Last modified July 09, 2013. http://www.ibtimes.com/us-exports-china-have-grown-294-over-past-decade-1338693.

The Conference Board, Inc. “Global Economic Outlook 2014, November 2013.” http://www.conference-board.org/data/globaloutlook.cfm.

Thomas, G. Scott. “Recession claimed 170,000 small businesses in two years.” The Business Journals . Last modified July 24, 2012. http://www.bizjournals.com/bizjournals/on-numbers/scott-thomas/2012/07/recession-claimed-170000-small.html.

United States Department of Labor: Bureau of Labor Statistics. “Top Picks.” http://data.bls.gov/cgi-bin/surveymost?bls.

Joyner, James. Outside the Beltway. “Public Financing of Private Sports Stadiums.” Last modified May 23, 2012. http://www.outsidethebeltway.com/public-financing-of-private-sports-stadiums/.

Siegfried, John J., and Andrew Zimbalist. “The Economics of Sports Facilities and Their Communities.” Journal of Economic Perspectives . no. 3 (2000): 95-114. http://pubs.aeaweb.org/doi/pdfplus/10.1257/jep.14.3.95.

Questions & Answers

how can chip be made from sand
Eke Reply
are nano particles real
Missy Reply
Hello, if I study Physics teacher in bachelor, can I study Nanotechnology in master?
Lale Reply
no can't
where we get a research paper on Nano chemistry....?
Maira Reply
nanopartical of organic/inorganic / physical chemistry , pdf / thesis / review
what are the products of Nano chemistry?
Maira Reply
There are lots of products of nano chemistry... Like nano coatings.....carbon fiber.. And lots of others..
Even nanotechnology is pretty much all about chemistry... Its the chemistry on quantum or atomic level
no nanotechnology is also a part of physics and maths it requires angle formulas and some pressure regarding concepts
Preparation and Applications of Nanomaterial for Drug Delivery
Hafiz Reply
Application of nanotechnology in medicine
has a lot of application modern world
what is variations in raman spectra for nanomaterials
Jyoti Reply
ya I also want to know the raman spectra
I only see partial conversation and what's the question here!
Crow Reply
what about nanotechnology for water purification
RAW Reply
please someone correct me if I'm wrong but I think one can use nanoparticles, specially silver nanoparticles for water treatment.
yes that's correct
I think
Nasa has use it in the 60's, copper as water purification in the moon travel.
nanocopper obvius
what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
How we are making nano material?
what is a peer
What is meant by 'nano scale'?
What is STMs full form?
scanning tunneling microscope
how nano science is used for hydrophobicity
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
what is differents between GO and RGO?
what is simplest way to understand the applications of nano robots used to detect the cancer affected cell of human body.? How this robot is carried to required site of body cell.? what will be the carrier material and how can be detected that correct delivery of drug is done Rafiq
analytical skills graphene is prepared to kill any type viruses .
Any one who tell me about Preparation and application of Nanomaterial for drug Delivery
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
The nanotechnology is as new science, to scale nanometric
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
Privacy Information Security Software Version 1.1a
Equilibrium price is a stable price and it must stay.discuss
Elvis Reply
Card 14 / 21: What are the similarities between a consumer’s budget constraint and society’s production possibilities frontier, not just graphically but analytically?
Ali Reply

Get Jobilize Job Search Mobile App in your pocket Now!

Get it on Google Play Download on the App Store Now

Source:  OpenStax, Principles of macroeconomics for ap® courses. OpenStax CNX. Aug 24, 2015 Download for free at http://legacy.cnx.org/content/col11864/1.2
Google Play and the Google Play logo are trademarks of Google Inc.

Notification Switch

Would you like to follow the 'Principles of macroeconomics for ap® courses' conversation and receive update notifications?