18 - IS-MP Analysis, Interest Rates and Output

Aggregate Expenditure

Aggregate Expenditure and Short Run Fluctuations

  • in the short run, changes in demand drive changes in outputs

    • can forecast SR fluctuations by predicting demand

  • aggregate expenditures describes everyone’s spending plans

    • analysis of business cycles starts by focusing on the demand side of the economy

    • aggregate expenditure = consumption + planned investment + government purchases + net exports

    • focus on planned investment — spending on new capital without inventory change — since we want how much people but and not unsold things accumulating

  • output adjusts to meet aggregate expenditure

    • when the total quantity of output exceeds aggregate expenditure businesses cut production and vice versa

    • macroeconomic EQ occurs when quantity output buyers collectively want to purchase equals to the quantity suppliers collectively produce

    • aggregate expenditure = GDP

    • in SR (year to years ups and down in business cycle ) demand conditions determines output

The Demand Driven Short Run and the Supply Driven Long Run

  • in LR, focus on the available supply of labour, capital, human capital, production function that summarizes state of technological progress

  • analysis explains economy’s potential output (uses all resources, sustainable)

  • in the SR GDP might not meet potential

    • economic slump can be an EQ bc businesses don’t want to make output that people won’t but and people won’t want to spend more since the economy is weak

  • when actual GDP exceeds potential, the economy will overheat, to keep up producers defer maintenance, run more shifts, pay overtime — not sustainable

  • output gap focuses on the balance between demand and supply side factors

    • output gap = (actual - potential)/potential * 100

  • supply side of the economy (labour, human and phyical capital, tech) grows smoothly over time so potential GDP grows smoothly over time

  • actual GDP moves in fits and starts, demand factors make it deviate substantially

  • EQ GDP is not potential GDP, it’s just where the economy rests where buying and producing is equal while potential is the highest sustainable level of production

The IS Curve: Output and Real Interest Rate

  • real interest rate represents the opportunity cost of spending (earning interest or buying more)

    • the higher r is, the more stuff you can buy if you wait till next year

    • it is the nominal interest rate adjusted for inflation which determines the year’s aggregate expenditure

    • policy makers use it to influence the economy, increasing it (and OC) to to reduce spending or reducing to increase spending

Aggregate Expenditure and Interest Rates

  • lower interest rates boosts consumption since there is a lower OC to buying (vs saving) and you have to pay back less on loans

    • the only group that reduces consumption is people who rely on interest payments for income (not a lot of people)

  • lower interest rates boosts investment for the same reasons (OC and actual cost)

  • lower interest rates boost government purchases

    • reduce cost of interest payments (transfer from government to who they borrow from) on government debt but doesn’t directly affect aggregate expenditute

    • low interest means there is more money in the budget to spend on other projects leading to an increase in purchases

    • not always true since extra funds sometimes used to pay debt

  • lower interest rates boosts net exports

    • makes the CA dollar cheaper which increases net exports

    • it takes fewer other currencies to buy a CA dollar so exports increase since CA stuff sells for fewer of other currencies than it did before (price cut)

    • cheaper CAD means it takes more money to buy imports from other countries so it decreases

IS Curve Links Real Interest Rate and the Output Gap

  • decrease in real interest leads to an increase in every component of aggregate expenditure

    • boost in investment is the most important since machinery and housing is very sensitive to the interest rate

  • lower interest rates boost aggregate expenditure

  • a rise in aggregate expenditure is matched by a rise in production and therefore GDP

  • potential output is determined by long run factors unaffected by business cycle changes

    • since it is unchanged, interest rate induced increase in output also increases output relative to potential output

    • more positive output gap

  • IS curve illustrates the link between interest rates, GDP, output gap

    • lowered interest leads to higher real GDP which leads to a more positive output gap

  • construct the economy’s IS curve by adding up the level of aggregate expenditure at each real interest rate

    • output adjusts to level of aggregate expenditure, this also reveals the GDP

    • just need to compare GDP to potential to calculate output gap at different real interest rates

  • IS curve (output on x, interest on y) is similar to demand in showing this year’s demand for all levels of output

    • also downwards sloping

    • lower real interest decr OC of making purchases thsi yr leading to more consumption

  • curve can be a straight line

Using IS Curve

  • change in the real interest rate leads to a movement along a fixed IS curve

    • curve is meant to illustrate how gap changes with interest so changing interest moves along the curve

  • changes in other factors will lead to the curve shifting

The MP Curve: What Determines Interest Rate

Bank of Canada

  • 8 times a year the governing council of the bank of CA meets to decide what to set the interest rate at

  • when the bank sets interest rates to influence economic policy, it is called monetary policy

  • sets nominal interest to influence the real interest

    • bank sets the nominal interest rate and knows inflation, therefore setting real interest

    • nominal - inflation = real

  • decisions effect the who economy

    • bank sets the policy interest rate which is the target for the overnight rate on a set of loans almost certain to be repaid the next day

    • loans are close to 0 risk so this can be thought as the risk-free interest rate

    • changes in the risk-free rate affect the interest rate you’re paid on savings and borrow money on

Risk Premium

  • the interest rate on a loan reflects the risk free rate plus a risk premium

    • banks and other lenders are paid for taking on risk

    • risk premium is the extra interest charged

    • real interest for borrowers = risk free rate + risk premium

  • risk premium is determined in financial markets

    • buying and selling complicated financial contracts allows big banks/financial institutions to reallocate risk in portfolios including what borrowers owe

    • risk premium is the price at which financial institutions are willing to bear the risk associated with lending you money, determined by supply and demand

MP Curve

  • MP stands for monetary policy which demonstrates the real interest rates and how changes in risk premium affect real interest

  • you can measure the risk premium using interest rate spreads

    • calculate the difference between the interest rate at which you borrow and the risk free interest rate (for loans of the same duration)

    • difference is the interest rate spread, an estimate of the risk premium

    • can use the interest rate for loans to the government since it is practically risk free

    • risk spread is normally low and stable but it will spike during a major financial crisis which corresponds in a rise in risk premium

  • MP curve is just a horizontal line because the bank just announces where it wants to set the interest rate and the curve reflects that plus the interest rate

IS-MP Framework

  • IS curve is how output gap depends on real interest rate

  • MP curve tells you what the real interest rate is

IS-MP Equilibrium

  • intersection determines the macroeconomic EQ, the level of output gap consistent with the real interest rate

Fluctuating Demand and Business Cycles

  • aggregate expenditure plays a central role in determining the macroeconomic EQ

    • can understand recessions and depressions as weak/declining aggregate expenditure

    • booms and busts of the business cycle reflect economy shifting between strong and weak demand

  • strong aggregate expenditure leads to a booming economy and full employment

    • when people are optimistic of the future, they will spend more money at any given interest rates

    • leads to an EQ with an output gap of 0 and GDP is sustainable and high

    • unemployment is low

    • economic outlook is good enough that people continue believing things will be good, EQ at good times

  • insufficient spending can lead to a slump and unemployment

    • decrease in aggregate expenditure at any given real interest rate and level of income due to pessimism leads to the IS curve shifting left

  • changes in aggregate expenditures create macroeconomic fluctuations

    • similar booms and busts occur in response to any factor that causes aggregate expenditure to shift at a given interest rate

  • recessions can be individually rational and collectively terrible

    • economic slumps create a macroeconomic EQ where economy produces less than potential and if nothing changes, prolonged recession will follow

    • once in a bad EQ, there isn’t a reason for buyers or sellers to change their plans because they are worried about a recession

Analyzing Monetary Policy

  • monetary policy shifts the MP curve

    • cutting the interest rate shigts the MP curve down leading to a new EQ with a higher GDP at a lower interest rate

    • they run out of steam once interest rates are brought down to 1%

    • cutting it to 0 would lead to no incentive to loan money vs storing it in a safe so it would have little to no effect

Analyzing Fiscal Policy an the Multiplier

  • fiscal policy is the government influencing the economy by adjusting its spending and tax policies

  • adjusting policy shits the IS curve

  • expansionary fiscal policy boosts aggregate expenditure, shifting IS to the right

    • shift by a change in government expenditures * multiplier

  • multiplier measures how much GDP changes as a result of direct and indirect effects from each extra dollar of spending

Macroeconomic Shocks

Spending Shocks that Shift the IS Curve

  • increased spending at any given real interest rate and level of income shifts the curve to the right

    • change in consumption * multiplier

  • consumption increases when people feel more prosperous — having more money to spend or believing they will soon have more money

    • stock market booms, housing prices — asset holders have more wealth

    • consumer confidence rise

    • government cuts taxes or increases assistance payments

    • redistributing income from those with higher incomes to lower incomes (transfer payments and tax system changes) increases consumption

  • investments increase when it’s profitable for the business to expand — believing new machinery investment will be profitable to expand

    • expanding economy so there is demand for products and need more capital equipment

    • high business confidence since capital investments are ling term so new equipment is bought depending on future profit expectations

    • lower corporate taxes increase after tax profits

      • investment rises with targeted investment tax credits that reduce the after tax cost of buying new equipment

    • lending standards and cash reserves, if it’s hard to borrow money at a reasonable rate, the best alternative is to invest in new equipment if your company has the cash on hand to do so

      • investment increases when loans are easier to get or businesses have large cash reserves (important if financial system isn’t working well)

    • uncertainty on economic outlook decreases investment

  • government purchases increase when fiscal policy expands economy

    • fiscal policy used to stimulate economy

    • government programs called automatic stabilizers automatically increase spending when economy is weak

    • outlets only directly increase aggregate expenditure and shift IS when it purchases g/s

    • programs simply transfer money from government accounts to recipient’s account so doesn’t directly increase sending, could indirectly increase by fiving money to people likely to spend it

  • net exports increase due to global factors

    • global economic growth so other economies have more money to spend and buy more products

    • exchange rate when CA becomes cheaper so CA goods become cheaper to foreign buyers so they buy more exports while imports fall

    • trade barriers are low so CA businesses have an easier time selling goods in foreign markets but it also increases imports so the net effect is unclear

Financial Shocks that Shift the MP Curve

  • changes in monetary policy with higher benchmark interest shifting real interest and the MP curve up

    • longer term interest rates are partially based on the current short-term interest rate and partially on expectations of future interest rates

    • banks will influence expectations, a signal that interest will rise is often enough to increase LT rate to shift MP curve up

  • financial market risks shift the risk premium, rise in risk premium shifts up real interest and the MP curve

    • default risk is increased risk borrowers will default and not repay loans at all or on time

    • liquidity risk is how banks can get cash by selling some of their loans to other lenders and occurs when there aren’t buyers or people willing to pay a reasonable price

    • interest rate risk is how interest rate offered today might be bad is future interest rates or inflation are unexpectedly higher, increasing uncertainty about future interest or inflation increases risk

    • risk aversion is lenders becoming more reluctant to take on risk, only willing at higher risk premiums

Predicting Economic Changes