CHAPTER 1
INTRODUCTION TO MACROECONOMICS
1.1 Some Basic Concepts
• Economics is the study of efficient allocation of resources in order to attain
the maximum fulfillment of unlimited human wants or needs.
• It is also defined as the study of how people make choices to cope with
scarcity and the science of making decisions in the presence of scare
resources.
• Macroeconomics that studies economy as a whole, which focuses on broad
issues such as growth, unemployment, inflation, trade balance, and etc.
• It is further subdivided into; theory and applied. Applied macroeconomics is
also subdivided into policy and econometrics.
• Economic theory is traditionally divided into two broad categories; macro
and macro economic theories
• A macroeconomic economic model is a deliberately simplified analytical
framework. A very rough skeletal representation of the economy.
• An economic model is a theoretical framework. It is an abstraction from the
real world.
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• A theoretical framework and model work can be mathematical or otherwise.
• When the economy is specified in mathematical framework, it is called
mathematical model whereas when it is specified in prose, it is called theory.
• The mathematical model is the best, it can enable us to have a number of
variables in problems.
• Mathematical model consists of equations which describe the structure of
the model.
• The equations will relate the variables to each other in a particular way.
• This equations are the assumptions or the axioms of the model.
• When the equations are subjected to mathematical operation, we get the
model solution.
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1.2 Nature of macroeconomic theory
• By nature it deals with aggregates and seek to explain the function and
performance of an economy as a whole.
• It does this by using what is referred to as economic indicators such as level of
national income, employment, general price level related inflation, interest rate,
trade imbalance and national debt
• There are 3 groups of macro-economic aggregates;
• Aggregates Variables
• Aggregates Markets
• Aggregates Sectors
Aggregates Variables include; Aggregate Output- when all commodities and
services produced in the economy over some period of time, all added together
by taking their monetary value.
Gross national products(GNP) = GDP + Net Income from abroad. Valuation of
GNP or GDP is either at market price or at factor cost. There is also Net
National Product (NNP) i.e. if depreciation is deducted from GNP.
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• Aggregate Net National Income(NNI) is the income of the nation as a
whole that recipient in an economy include; individuals, business firms and
governments.
• Aggregate Expenditure which is the sum of all final expenditure by
residents in the country that consists of consumer expenditure, government
expenditure, gross capital formation.
• GNI and GNE are identical in value and their relationship is shown in what
is called the circular flow
• Other aggregate variables include; Price Level (P), Interest Rate (R) and
Employment (N).
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Market Aggregates include:
• Output market,
• Labor market,
• Money market,
• Bond market and
• Foreign exchange market
Aggregate sectors: are obtained through aggregation of the markets. Two
major sectors include;
• The Real sector which consist of the output and labor markets
• The Financial sector consisting of money and bond markets.
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1.3 Historical Perspectives of Macroeconomics
• Macroeconomics was originated from the classical economist, most of them
from Britain and France and other part of Europe.
• Before the coming of Keynes, macroeconomics primarily focused on the theory
of output and employment.
• With the coming of Keynes macroeconomics turn a new branch, and he took
the classical economists to task.
• Keynes replaces the classical economists concept with his own broad and new
concept of macroeconomics
• The Twentieth-century developments in Macroeconomics: Evolution or
Revolution?
• Blanchard (2000) argues the history of macroeconomics in the twentieth
century appears as a series of battles, revolutions, and counterrevolutions, for
example;
• The Keynesian revolution of the 1930s and 1940s,
• The battles between Monetarists and Keynesians of the 1950s and 1960s,
• The Rational Expectations revolution of the 1970s, and
• The battles between New-Keynesians and Neoclassical of the 1980s.
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• In surveying, the development of macroeconomics over the course of the
twentieth century, Blanchard identifies three epochs, namely:
• pre-1940, an epoch of exploration;
• 1940–80 of consolidation; and
• post-1980 of a new epoch of exploration
According to Blanchard, among the ‘steady accumulation of knowledge’
that took place over these periods, it is possible to identify a number of
examples, which include:
• Improvements in the availability of economic data in developing a system of
national accounts;
• The development and improvements in econometric methods in more
detailed modelling of the behavioral relationships of variables;
• The construction of macro-econometric models of the economy;
• The incorporation of the expectations-augmented Phillips curve analysis into
macroeconomic models and more careful modelling of how expectations
are formed;
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• An examination of the Friedman stabilization policy implications and of
Lucas (1976) rational expectations for the analysis of policy changes.
• However, in contrast, Woodford (2000) argues that even though there has
been a progress over the course, macroeconomics ‘has been famously
controversial and it is sufficiently far from transparent’.
• Acknowledging the discussions of the twentieth-century of the developments
in macroeconomics makes frequent references to revolutions and counterrevolutions’, Woodford traces the development of macroeconomics in
historical perspective.
• Starting from Keynes’s (1936) General Theory, Woodford tracks progress in
macroeconomics from the Keynesian revolution to neoclassical synthesis,
the Great Inflation to the crisis in Keynesian economics, monetarism, rational
expectations and the new classical economics, real business cycle theory to a
new neoclassical synthesis.
• From Woodford’s historical perspective, the evolution of economists’ thinking on
macroeconomics has been far from smooth.
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1.4 Macro-economic objectives
• The objective is to simply deal with the macro-economic problems. For
example, we want to have;
- high income level
- high growth rate
- supply trade balance as to have high foreign exchange.
- low interest rate
• These are usually the objectives specify in national development plans.
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1.5 Areas of Macroeconomic Research
• The two main areas of macroeconomic research are long-term economic
growth and shorter-term business cycles
• Long-term economic growth refers to an change in real GDP per-capita,
change in the national income and others over a long period in an economy.
• Shorter-term business cycles, which involves the causes and consequences
of short-term fluctuations in national income, employment and other
macroeconomic variables.
• Evidence suggests that money plays an important role in generating business
cycles, the upward and downward movement of aggregate output produced
in the economy.
• Business cycles affect all of us in immediate and important ways. When
output is rising, for example, it is easier to find a good job; when output is
falling, finding a good job might be difficult
• Macroeconomists try to understand the factors that either promote the
economic growth such as support development, progress, and rising living
standards or retard economic growth.
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• Superimposed over long-term macroeconomic growth trends and the
levels and rates of change of significant macroeconomic variables such as
employment and national output go through fluctuations.
• These fluctuations involve expansions, peaks, recessions, and troughs.
• When plotted on a graph, these fluctuations show that businesses perform
in cycles; thus, we call it business cycle.
• For example, the United States National Bureau of Economic Research
(NBER) measures the business cycle, which uses GDP and Gross
National Income to date the cycle.
• The NBER is also the agency that declares the beginning and end of
recessions and expansions.
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1.6 Macroeconomic Issues
• Economists are always interested in how economies work, what makes them
more or less successful than other economies.
• To do this, economists use information gathered from the economy to
conduct analyses that give an idea of how the economy is performing.
• The factors that explain the macroeconomic performance of an economy are
known as macroeconomic issues.
• Macroeconomic issues are the concerns surrounding the factors that explain
macroeconomic performance. For example, concerning roads alone,
economists can look at how many roads have been constructed, the time each
construction took, the materials that were used for each construction, and etc.
• It can be difficult to navigate all these considerations in one shot and explain
it to others, and hence, economists focus principally on Gross Domestic
Product (GDP), unemployment, and inflation among many others.
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1.6.1 Gross Domestic Product
• Real Gross Domestic Product(GDP) is a measure of the value of all
final goods and services produced in an economy during a given period,
adjusted for inflation.
• The real GDP is one of the macroeconomic issues because it is an
important indicator of whether the economy's output is growing or
declining.
• Obviously, if the economy's output is declining, then that economy has
faced a serious problem and this is why economists are so concerned
about the real GDP.
• How will we know if the economy's output is growing or declining?
Simple, we will compare the previous year's real GDP to the current
year's real GDP so that we know how the real GDP is one of the
macroeconomic issues.
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• Gross Domestic Product (GDP) is the total market value of all final
goods and services produced within a country in a given period of time.
• Final goods are those goods sold to their final users and those will
disappear in the process of the production of some other for-sale
good
• It is also the total expenditure on all final goods and services produced
within a country in a given period of time.
• It is a measure of a country’s total income earned from all productive
activity in the domestic economy.
̶ When judging whether an economy is doing well or poorly, it is
natural to look at the total income that everyone in the economy is
earning.
̶ There are other measures of total income, but GDP is the most
popular measure.
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• The main difference between nominal GDP and real GDP is the total market
value of all final goods and services produced within a country in a given
period of time is calculated based on current price and constant price
respectively.
• The nominal GDP market value is calculated using current prices, the prices
that prevailed when the production takes place.
• The real GDP value is calculated using constant prices, the prices that prevailed
in a benchmark year called the base year.
• However, goods that doesn’t disappear in the process of the production of some
other for re-sale good are called intermediate goods.
• If intermediate goods are considered as final goods, GDP is counted twice that
is not good.
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• How to measure GDP/GNP?
• Gross national product (GNP): Total market value of the final goods and
services produced by a nation’s economy during a specific period of time,
usually a year, which involves the depreciation or consumption of capital used
in the process of production.
• It becomes net national product (NNP), after reduction of allowance from
GNP.
• We can measure GDP/GNP in 3 methods: Value added of production, Income
and Expenditure methods
Value added of production method-The sum of value added: the difference
between the sum of revenue and cost.
• Accounted for all sectors of the economy e.g., agriculture, construction,
manufacturing, trade, finance, services, etc.
Income method: Income earned by all factors of production. It involves:
• Employee compensation
• Rents (return to housing)
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• Interest payments (return to lenders of capital)
• Payment to owners (return to capital)
• Indirect business taxes (return to government)
Expenditures method: GDP = Consumption +Investment +government
spending + Net Export
• Is GDP a good measure of economic well-being? No, but it is the best one
measure we have.
• There’re a lot that’s missing in GDP, for instance, work done in
home, volunteer work, illegal work, leisure, environment, disasters,
etc.,
• GDP doesn’t count volunteer work, ignores environmental damage,
and consumer surplus.
• In addition, in consumer surplus there are free digital technology
such as free applications, Google, Google maps, Wikipedia, Open
Office, YouTube and freely available education. Therefore, none of
these adds to GDP.
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Some economists can also use the following indicators to measure economic
performance. These indicators are:
Consumer spending indicators: Measure how much capital consumers feed
back into the economy
Income and Savings indicators: Measures how much consumers make and
save
Industry Performance indicators: Measures GDP by industry
International Trade and Investment indicators: Indicates the balance of
payments between trade partners, how much is traded, and how much is
invested internationally
Investment in Fixed Assets indicators: Indicate how much capital is tied up in
fixed assets
Employment indicators: Shows employment by industry, state, county, and
other areas
Government indicators: Shows how much the government spends and receives
Special indicators: All other economic indicators, such as distribution of
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being,
and more
1.6.1.1 Nominal and Real GDP Relationship
Nominal GDP: An economic statistic measured using actual market prices,
which are not adjusted for inflation .
Real GDP: An economic statistic measured after it has been adjusted for
inflation using constant price..
Real GDP per-capita- is one of the best available measures of long-term
economic growth. For example, the real GDP of the United States in 2018
was $20,580.2 billion and mid-year of 2018 population was estimated about
327,436,000, the per-capita real GDP was $62,853.
• If we know that GDP is the measurement of everything that is produced,
we should also ask the question, who buys all of this production? This
demand can be divided into four main parts:
i. Consumer expenditure (consumption)
ii. Investment expenditure
iii. Government expenditure on goods and services
Iv. Net export expenditure
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Year
Product One
Price ($) Quantity
Product Two
Price ($)
Quantity
2015
50
10
20
50
2016
100
20
30
100
2017
150
20
50
200
Nominal GDP
$
Growth Rate (%)
2015
($50 ✕ 10) + ($20 ✕ 50) =
1500
2016
($100 ✕ 20) + ($30 ✕ 100) =
5000
[(5000 – 1500)/ 1500] ✕100 = 233
2017
($150 ✕ 20) + ($50 ✕ 200) =
13000
[(13000 – 5000)/ 5000] ✕100 = 160
Real GDP (Base year 2015)
$
2015
($50 ✕ 10) + ($20 ✕ 50) =
1500
2016
($50 ✕ 20) + ($20 ✕ 100) =
3000
[(3000 – 1500)/ 1500] ✕100 = 100
2017
($50 ✕ 20) + ($20 ✕ 200) =
5000
[(5000 – 3000)/ 3000] ✕100 = 67
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• In order to see how much production has actually changed, we need to
extract the effects of higher prices on nominal GDP, so that what we’re left
with the real GDP, the changed in the quantity of goods and services
produced.
• This can be easily done using a concept known as the GDP deflator. It is a
price index measuring the average price of all goods and services included
in the economy.
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Year
Product one
Product two
Price ($) Quantity
Price ($)
Quantity
2015
50
10
20
50
2016
100
20
30
100
2017
150
20
50
200
Nominal GDP
$
GDP Deflator
2015
($50 ✕ 10) + ($20 ✕ 50) =
1500
(1500 / 1500× 100 = 100
2016
($100 ✕ 20) + ($30 ✕ 100) =
5000
(5000 / 3000) × 100 = 167
2017
($150 ✕ 20) + ($50 ✕ 200) =
13000
(13000 / 5000)× 100 = 260
Real GDP (Base year 2015)
$
2015
($50 ✕ 10) + ($20 ✕ 50) =
1500
2016
($50 ✕ 20) + ($20 ✕ 100) =
3000
2017
($50 ✕ 20) + ($20 ✕ 200) =
5000
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1.6.1.2 The GDP Deflator and the Inflation Rate
• The GDP deflator is a measure of the overall level of the prices of the
final goods and services produced within a country during a given period
of time
• And its growth rate is, therefore, a measure of the rate of inflation which
is given by
See the following example to clearly understand how it can be calculated.
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Year
Product One
Product Two
Price ($)
Quantity
Price ($)
Quantity
2015
50
10
20
50
2016
100
20
30
100
2017
150
20
50
200
Nominal GDP
$
GDP Deflator
2015
($50 ✕ 10) + ($20 ✕ 50) =
1500
(1500 / 1500) ×100 = 100
2016
($100 ✕ 20) + ($30 ✕ 100) =
5000
(5000 / 3000) ×100 = 167
2017
($150 ✕ 20) + ($50 ✕ 200) =
13000
(13000 / 5000) ×100 = 260
$
Rate of Inflation (%)
Real GDP (Base year 2015)
2015
($50 ✕ 10) + ($20 ✕ 50) =
1500
2016
($50 ✕ 20) + ($20 ✕ 100) =
3000
2017
($50 ✕ 20) + ($20 ✕ 200) =
5000
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• The GDP Deflator were 167 and 260 in 2016 and 2017, respectively. These
indicate that 167 and 260 percentage in prices of the corresponding to the 2016
and 2017 domestically produced of the final goods and services in relation to
the 2015, as a base year.
• Why were the goods produced in 2016 and 2017 worth 0.67 and 1.60 times as
much as at 2015 prices?
• It must be that 2016 and 2017 prices were 0.67 and 1.60 times as high as 2015
prices , on average. This is what the GDP Deflator is saying.
• The reason why we need a GDP deflator is that the nominal GDP changes
from one year to the next partly because of inflation and the real GDP, on the
other hand, changes because of changes in production alone.
• Therefore, GDP deflator can convert nominal GDP to real GDP by deflating
the effect of inflation in nominal GDP.
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❖Consumer price index is another one, which is calculated as the price of the
basket of goods and services in each year is divided by the price of the basket in
the base year, and this ratio is then multiplied by 100%.
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1.6.1.3 Methods for GDP growth calculations
• There are two types of methods for GDP growth calculations: discrete
and continuous methods.
• Suppose GDP grows at 4% per year. What is its level after 5 years? What
is the cumulative percentage growth over 5 years?
• Example1. Assuming our GDP is growing in jumps, i.e. discretely we use
the formula.
The cumulative percentage growth is then
Example 2. If a discrete growth GDP is growing at 5% annually, how long
does it take to double?
Since GDP doubles in x years,
, which means,
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The GDP of an economy growing 5% annually will double in a little over 14
years.
Method 2. If the GDP grows continuously, we apply
The cumulative factor in method 2 is 1.2214 compared to 1.2166 in method 1,
which is what we expected: cumulative growth is always higher in the continuous
compared to the discrete case.
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If a continuous growth GDP is growing at 5% annually, how long does it
take to double?
Solution:
Taking natural logs of both sides of this equation, one obtains
Since,
GDP will double in less than 14 years, i.e. faster compared to the case of
discrete growth.
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Example: GDP was measured in a country and rose from $256,501 million
in 1948 to $988,338 million in 2002, What was the average annual growth
rate?
Method 1: discrete growth.
Plugging in the values for GDP levels in 1948 and 2002, we obtain:
Take natural logs of both sides of this equation:
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Method 2: Continuous growth.
As expected, in case of a continuous growth formula, we can get a lower annual
growth rate since continuously growing variables grow to a higher level during
the same period of time compared to their discrete analogues if the nominal
growth rate is the same.
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1.6.2 Unemployment as a macroeconomic issue
-Unemployment is an important macroeconomic issue as it means that the
country is not using one of its largest inputs - labor.
• Unemployment means that individuals who are unable to get a job even
though they are willing to work and are actively looking for work.
• So, why is this a macroeconomic issue?
• First, the goal of economics is to satisfy the needs of the people with the
limited resources available. If the economy is not able to satisfy the job
needs of the people, then it is failing. So, we can imagine why economists
take unemployment so seriously.
• Second, labor is one of the factors of production, if the economy is leaving
some labor on the table unused, then it is not producing to its optimal
potential, and something needs to be done about it.
• Outside these typically economic considerations, economists also suggest
that high rates of unemployment can contribute to high rates of crime,
political unrest, high rates of depression, and generally poor well-being for
unemployed people.
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▪ Seasonal unemployment is happened due to season changes, for example
in Ethiopia during harvesting crops the amount of unemployment is low
comparing to summer season
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1.6.3 Inflation as Macroeconomic Issues
• The average price of goods and services in an economy is called the
aggregate price level or, more simply, the price level.
• Inflation, a continual increase in the price level, affects individuals,
businesses, and the government.
• It is generally regarded as an important problem to be solved and is often at
the top of political and policymaking agendas.
• To solve the inflation problem, we need to know something about its causes.
• Inflation is a serious macroeconomic issue because it represents a rise in the
overall level of prices in an economy.
• It is the rise in the overall level of prices in an economy. It is an issue when
the incomes of households do not rise with the prices and is a real problem
because it makes life difficult for people.
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• Inflation rate : It is a measure of how fast the annual rate of change of
the overall level of prices in the economy.
• A very high inflation rate, more than 20 per cent a month that can cause
massive economic destruction, as the price system breaks down and the
possibility of using profit loss to make rational business decisions
vanishes. Such episodes of hyperinflation are among the worst economic
disasters.
• Moderate inflation rate is a little more than 10 per cent a year, should
not seriously compromise consumers’, investors’, and managers’ ability
to determine the best use of their financial resources.
• Misery Index: the sum of the inflation and unemployment rates as a
measure of how bad/miserable the economy is. Some times we call it
stagflation.
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• The price level and the money supply generally move closely together.
• These data seem to indicate that a continuing increase in the money
supply might be an important factor in causing the continuing increase in
the price level that we call inflation
• Further evidence that inflation may be tied to continuing increases in the
money supply.
• Because money can affect many economic variables that are important to
the well-being of an economy, politicians and policymakers throughout
the world care about the conduct of monetary policy, the management of
money and interest rates.
• The organization responsible for the conduct of a nation’s monetary
policy is the central bank.
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• Assume that a family has an income of Birr 3000 and purchases 3 kilogram
of sugar each month for Birr 100 per kilogram. The price of a kilogram of
sugar suddenly increases to Birr 150, and this means the family can only
afford 2 kilograms of sugar in that month.
• If the prices of goods increase suddenly and the income of households
remains the same, the households struggle to survive since they can't afford
the same quantities they used to buy with their income.
• Therefore,, the family will go hungry at some point since they only have 2
kilograms, but they actually need three kilograms of sugar.
• Here's another problem caused by inflation, suppose you've been saving Birr
500,000 to buy your dream house. You finally make it to the Birr 500,000,
only to be told that the price of that house is now Birr 750,000. O! It’s
painful!
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In general most governments, therefore, have to ask and answer a series of related
questions to address these issues:
• Reducing the impact of recessions by reducing fluctuations in the shortrun - The governments must seek to reduce how often market conditions
change within a year. This helps reduce the pressure felt by the people in terms
of inflation and unemployment.
• Reducing short-run fluctuations through monetary policy - governments
should seek to alleviate the effects of macroeconomic fluctuations by
manipulating interest rates, tax rates, or government spending.
• Maintaining economic growth in the long-run -governments must be
concerned with ensuring that the economy constantly grows, as declines in
growth result in unwanted issues like inflation and unemployment.
• Managing the trade-off between lower unemployment rates and higher
inflation rates - As more people work, they have higher spending power and
demand more. This results in increased prices, hence, inflation. Therefore,
governments must seek to manage the trade-off between unemployment and
inflation.
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1.6.4 Other Macroeconomic Issues
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