Monday, July 17, 2006

Government Surplus

An email from a student:

Will-

I just looked at the correct reponses to the most recent homework, and I
was curious about the last question. In the book, it says that if the
government faces a budget surplus, it will use that money to pay for some
of the national debt. Therefore i thought the graph should remain
unchanged. But the correct answer showed a shift of the supply curve in the
right direction. I was wondering why this was?

Thanks,

[name withheld]


The short answer is that in this model government surpluses are considered savings. Increased savings shift the supply curve to the right. Debt plays no role in the market for loanable funds.

The long answer: I'm not sure if the Professor has shared with you the national income accounts identity:

Y = C + G + I

This equation just says that income (Y) has to equal expenditures (consumption, C, and government spending, G) plus investment. From an individual's point of view, this equation makes sense, you either save or spend your income. The model we're studying in this class takes that insight and aggregates across all individuals in the economy. The only difference is we add in the government.

You can re-write the equation:

Y - C - G = I

and because taxes (T) are paid by individuals and taken in by the government as revenue, you can add and subtract T from the left hand side and re-write as:

(Y - C - T) + (T - G) = I

This new equation just says private savings (income minus taxes and consumption) plus public savings (government revenue minus government spending) equals investment. This is our equilibrium condition in the loanable funds market with the left side of the equation supply and the right side demand.

For our problem then (T - G) got bigger making the left side of the equation (supply) bigger.
...

By the way, I share your confusion with this problem. While the above analysis 'works' (and you should make sure you understand it and can reproduce it for the exam tomorrow), I'm not clear as to the mechanism for government surpluses to increase supply. *How* do surpluses increase the supply for loanable funds? I dunno.

The flip side, government deficits, is easier to see, IMHO. With deficits, the government must borrow funds. This borrowing 'crowds out' private investment, i.e. the supply for funds goes down.

Exam II review session

7:10 to 8 pm tomorrow Tuesday the 18th in 184 Young

Wednesday, July 12, 2006

Why does growth matter?

You can come up with many reasons why growth matter and many reasons why it may not matter. Go ahead. You can do it.

Consider this: The growth rate in the 60's was such that incomes were doubling about once a generation (25 years). The 80's show a different trend where incomes were growing such that they only doubled once every generation and a half.

In broad strokes how would you characterize each of these decades in terms of civil rights, political atmosphere, social justice or any other dimension? To what extent can these differences (if there are any) be attributed to the differences in the growth rates?

Practice with Real US Data

Data:





























YearNominal GDP (Billions) Population (thousands) CPI (1983=100) Labor (Billions of hours)
1960 526.4 179979 29.6 94
1980 2789.5 227225 82.4 126
2000 9817 282192 172.2 193

Source 1. Source 2.

Questions:
  1. What's GDP per person? Growth?
  2. What was inflation in each period?
  3. What was labor productivity?
  4. would hourly compensation be in the year 2020 if:
    1. The rate of increase from 1960-1980 continued to 2020?
    2. The rate of increase from 1980-2000 continued to 2020?

Gapminder

Gapminder is a great tool to visualizing relationships between various development data.

The most interesting views take income on the horizontal axis and the following on the vertical axis (using default settings):

  • CO2 emissions
  • Child mortality
  • Life expectancy
  • Children per woman
  • % of girls in school
  • Phones per capita
  • Internet per capita

Household Expenditure Shares 1901/2002













Item19012002
Apparel 14%4%
Food and Beverages 43%13%
Housing 23%33%
Entertainment2%5%
Transportation0%19%
Healthcare/Insurance5%16%
Education1%2%
Charity1%3%
Booze/Tobacco3%2%
Other 8%3%


Source.