[There were just two lectures this week, since the first exam was on Wednesday. The material corresponds to parts of Case & Fair's Chapter 7.]
LECTURE 13
Mon., Feb. 21, 2000
0. IMPEDIMENTA
* Today: GDP accounting, continued
I. A bit more about GDP and
GNP
II. Pros and cons of GDP
III. Go over Problem Set 3
* FIRST EXAM IS WEDNESDAY
-- It covers through: today's lecture / Problem Set 3 / Chapter 7
---- What to focus on, in order of importance:
------ (1) the three problem sets (and their solution sheets)
------ (2) the lecture notes (check your own notes against these Internet
versions of my notes)
------ (3) the book chapters
-- Solutions to Problem
Set 3 have been posted on the Internet
I. A BIT MORE ABOUT GDP AND GNP
Comparing GDP and GNP: Going back to the definitions of the two, they
are the same except for the final phrase:
"located within a country" (GDP) vs. "owned by a country's citizens"
(GNP).
-- Exs.:
---- My teaching services in this classroom: counted in U.S. GNP, because
I'm an American citizen, and U.S. GDP.
---- The teaching services of a visiting faculty member from Holland:
not in GNP, because he's not a U.S. citizen, but it is in GDP.
---- A car produced at a Subaru plant in Indiana, owned by Japanese
but using American labor: some of its output is in GNP; all
of its output is in GDP.
---- A car produced at a Subaru plant in Japan: none of its output
is in U.S. GNP or GDP.
National income and product accounting (NIPA), like macro, itself
is a relatively new phenomenon, and was invented in the 1930s.
-- Recall that John Maynard Keynes published The General Theory
in 1936, during and largely as an answer to the Great Depression.
-- Simon Kuznets, the father of national income accounting (and
later a recipient of the Nobel Prize in economics), published his first
estimates of U.S. national output in 1934 and continued to do so through
the 1940s. Kuznets estimated U.S. output retroactively to 1869.
Historical note: In the 1940s, during World War II, the U.S. and England had national income accounting, and Hitler's Germany did not. That knowledge about national production capabilities made a tremendous contribution to the Allies' military victory.
Calculating the level of GNP or GDP is not easy -- the U.S. Commerce
Department employs huge teams of economists and accountants to crunch out
the "National Income and Product Accounts" (NIPA).
II. PROS AND CONS OF GDP
Q: Why should you care about what the level of GDP is?
A: GDP has been called a country's "economic report card."
It's not bad as a bottom-line measure of how a nation is doing economically.
Per-capita GDP is a reasonable measure of a country's standard of living. In fact, "standard of living" and "per capita GDP" have come to be virtually synonymous. Higher per capita GDP <==> on average, people eating better, living in better dwellings, healthier, better clothed, better educated, consuming more luxuries, etc.
A large absolute GDP ==> a powerful country (politically,
militarily, diplomatically)
-- The U.S., with the world's largest GDP by far, is also "the world's
only remaining superpower." Like the 900-pound gorilla that sits wherever
it wants, an economic powerhouse like the U.S. wields enormous influence
in world politics.
Also, you should care because it's an essential part of macro. Economics is about measuring social data as well as interpreting it. Most people would agree that interpreting the data is a lot more fun-- e.g., arguing over whether Reagan's supply-side policies worked or didn't work -- and we'll get to that soon in this course. But for now, let's learn a bit about what the data looks like and where it comes from.
GDP as the nation's "economic report card"? Obviously a bit limited. Economist Paul Krugman, by contrast, stresses three "Roots of Economic Welfare":
1. Productivity Growth
-- (Productivity = Output per worker, or Output per worker-hour)
-- very similar to per-capita GDP (= GDP/population)
2. Income Distribution (i.e., should not be too skewed
in favor of rich)
3. Job Creation
-- Krugman: "If these things are satisfactory, not much else can go
wrong [in the economy]. If they are not, nothing can go right."
-- Note: #1 and #3 are closely related to GDP growth. Productivity
growth generally translates into per-capita GDP growth, and rising GDP
is generally associated with rising employment.
-- #2 implicitly makes the obvious point that if most of the gains
in national income are going to a very small slice of the population, then
most people's "economic welfare" won't be improving much. And, in fact,
according to economist Paul Krugman, in the 1980s, 66% of the after-tax
gains went to the top 1% of wage-earners.
-- In an earlier lecture we noted that the distribution of U.S. income
is very uneven. The distribution of world income, as measured by
GDP, is even more uneven.
-- The U.S., "Euroland," and Japan together account for 71%
of world economic output.
---- ("Euroland" = the 11 Western European countries that are adopting
a common currency, the "Euro")
Other limitations of GDP and NDP:
1. They omit depreciation of the environment.
-- Ex.: If a 3rd-World country cuts down 1 million acres of rainforest
in a year to sell timber, the depreciation of the chainsaws and the logging
trucks is counted as depreciation, but the depreciation of the rainforest
itself is not.
-- Ex.: Exxon Valdez spill was good for GDP! Poisoning of Prince
Wm. Sound does not count against GDP, but payments to cleanup crew count
towards
GDP.
2. They omit important household services, especially those that
are normally performed by women (e.g., child-rearing, cooking, and cleaning).
-- Such activities are only counted when you pay someone else to do
them (and report that income/payment to the government). Granted, the word
"market" doesn't apply to these services when homemakers perform them for
free, but when a household hires a maid or a nanny or a cook, those services
are counted in GDP. Moreover, not every entry in GDP is a transaction where
money changes hands-- ex., "imputed" rent from owner-occupied houses.
-- Ex.: 1950s family: Dad earns $50,000/year, Mom raises their two
children, cooks, cleans, etc. Then, Dad gets laid off and takes a lower-paying
job and Mom takes job, such that both now earn $25,000/year. They pay a
nanny $10,000/year, a cook $10,000/year, and a maid $10,000/year. The family
is almost certainly worse off, yet they're now contributing a lot more
to GDP than before.
-- Ex.: Two welfare mothers who currently stay home and take care of
their kids. Neither is contributing to GDP. Under new reforms, they leave
welfare and get jobs, taking care of each other's kids. Now the
work they do is counted in GDP.
3. They count military and wartime spending that provide no tangible
good or service. While one could think of military spending
as providing a service (or "public good") in the form of protection against
foreign aggressors, GDP pioneer Simon Kuznets himself advocated a "peacetime"
concept of GDP and said:
"there is little sense in talking of protection of life and limb
against external enemies as an economic service to individuals -- it is
a precondition of such service, not a service in itself."
4. They omit the value of leisure time.
-- If many Americans are "running faster and faster just to stay in
place" -- i.e., working ever-longer hours without seeing much of a rise
in their pay -- they are probably worse off, yet GDP wouldn't reflect their
forgone leisure time.
-- In a recent book called The Overworked American, Harvard
economist Juliet Schor argues that Americans' work weeks are the longest
of any major industrialized country and that the typical American's work
week has gotten much longer in recent years.
-- Historical example: After Emancipation in 1865, the total labor
supply of former slaves in the American South fell by one-third. Per-capita
income per capita went
down because people -- namely the ex-slaves
were
better off. Instead of being compelled to work in the fields
from sunup till sundown, they now had the options of working less (consuming
leisure) or spending more time in household production (fixing up their
houses, sewing their own clothes, etc.). Clearly their quality of life
had greatly improved, yet the South's per-capita GDP would have fallen
off greatly.
Alternative measures of economic well-being:
Net Economic Welfare (N.E.W.), invented by two Yale economists,
William Nordhaus and James Tobin, in 1972.
-- Start with NNP (Net National Product), modify as follows:
+ value of leisure time
+ underground economy (excludes illegal activities,
but includes under-the-table services such as babysitting, etc.)
- environmental damages
...
==> N.E.W. has been growing steadily, but also more slowly, than NNP
since 1929.
Since 1940, N.E.W. <
NNP.
Genuine Progress Indicator (GPI), created in the 1990s by a group
in San Francisco (Redefining Progress). Like the N.E.W., it takes
into account environmental damages and leisure time. It also adds in the
value of unpaid household production and subtracts out spending on services
like anti-theft devices and private bodyguards that are purchased merely
as protections against social ills like crime.
III. GO OVER PROBLEM SET 3 (PS3) -- [you kind of had to be there...]
PS3 was the mini-PS that you were supposed to do over the weekend. The
problems were:
CASE & FAIR, CHAPTER 7, #1, 2, 5, 7, 9.
Solutions were
posted on the Internet before noon today.
***
Wed., Feb. 23, 2000: FIRST EXAM
***
PRINCIPLES OF MACROECONOMICS
WEEK 5, LECTURE 14
Fri., Feb. 25, 2000
Today:
I. Nominal vs. real GDP
II. Go over first exam
I. NOMINAL VS. REAL GDP
A few items for your consideration:
Defn. REAL: adjusted for inflation; relative to the prices of other goods or other years.
Defn. NOMINAL: measured in current dollars, without regard to other prices or purchasing power.
Defn. NOMINAL GDP: GDP measured in current dollars; computed
by adding up the market value of all final goods and services produced.
-- How we compute nominal GDP: For each good or service, total up the
quantity produced (q) and multiply it by the price (p) of
that good or service. Then add all of those values together (the product,
p*q,
of each good), and their sum is nominal GDP.
-- Shorthand: nominal GDP = Spiqi,
where i is each good or service.
|
-- Ex.: A small island economy, which produces just three goods -- beer, pretzels, and bicycles. Using hypothetical prices and quantities of those goods, we can compute nominal GDP as follows:S is the Greek letter "sigma" and it means "summation," or "sum of."
| Commodity | p | q | p times q |
| Case of beer | $20 | 100 | $2000 |
| Bag of pretzels | $1 | 100 | + $100 |
| Bicycle | $200 | 10 | + $2000 |
| TOTAL GDP | $4100 |
Defn. REAL GDP: GDP measured in constant dollars, i.e. the prices of a "base" year. Ex.: 1992 nominal GDP was $6 trillion, 1992 real GDP was $5 trillion in 1987 dollars.
Now for some notation:
Q = real GDP
P = price index
-- P = 100 for a base year (say, 1992) that we use to compute
real GDP
\
The price index is really a percentage of the base year's price
level. So it's equal to 100% in the base year.
-- The price index we'll be using today is the GDP price index,
or GDP deflator, which is used for converting nominal GDP into real GDP.
It's also our broadest measure of the general price level.
Now, here's how to compute real GDP from nominal GDP:
Real GDP = (Nominal GDP)/[(GDP Price Index)/100]
or, writing the same thing in our shorthand
notation:
Q = (Nominal
GDP)/(P/100)
-- In the base year, when P=100, nominal GDP and real GDP will always
be equal.
-- In years when P > 100, real GDP will be less than nominal
GDP.
-- In years when P < 100, real GDP will be greater than nominal
GDP.
To compute nominal GDP from the GDP price index (P) and real GDP (Q):
Nominal GDP = (P/100) * Q
To compute the GDP price index (P) from nominal GDP and real GDP (Q):
P = [(nominal GDP)/(real GDP)] *100
[At this point we worked through some examples of calculating real GDP from PQ and P, and also calculating P from PQ and Q. With a calculator, these computations are easy.]
-- Exs.:
| Year | Nominal GDP
(billions$) |
Real GDP
(billions$) |
GDP price index |
| 1992 | 6244.4 | 6244.4 | 100.00 |
| 1993 | 6558.1 | 6389.6 | ______ |
| 1995 | 7265.4 | ______ | 107.76 |
-- The base year is 1992. We know that because the price index (P) = 100 in 1992.
-- Now, let's fill in the blanks:
---- Real GDP in 1995 = (nominal GDP)/(P/100) = 7265.4/(107.76/100) = 7265.4/1.0776 = 6741.3
---- GDP price index in 1993 = ((nominal GDP)/Q) * 100 = 6558.1/6389.6
(*100) = 1.0264 * 100 = 102.64
II. GO OVER FIRST EXAM
[I presented summary statistics, showed an overhead of the answers (also available online), and handed back the exams. Next week we'll go over a few items from the exam.]