110 likes | 341 Views
Inflation and Disinflation. Inflation is the overall increase in prices = increase in price level Changes constantly Hard to predict Higher rates of inflation = harder to predict a nticipated inflation Unanticipated inflation Bank of Canada is committed to keep inflation at about 2%/year.
E N D
Inflation is the overall increase in prices = increase in price level • Changes constantly • Hard to predict • Higher rates of inflation = harder to predict • anticipated inflation • Unanticipated inflation • Bank of Canada is committed to keep inflation at about 2%/year
Inflation in AD-AS model: • Changes in wages • Increase in wages shifts AS upward • Increases in other factor prices also shift AS upward • We have seen what happens when Y = Y* • Unemployment rate = natural rate of unemployment • Terminology: natural rate of unemployment ≡ non-accelerating inflation rate of unemployment, NAIRU • Mark it as U* • NAIRU = frictional rate + structural rate
Changes in wages • Inflationary gap • Can come from a positive AD shock • There is an upward pressure on wages • Because there’s increased demand for labour • Recessionary gap • Can come from a negative AD shock • There is an downward pressure on wages • Because there’s idle labour • Y = Y* • No pressure on wages • Expected inflation • Signing a labour contract • Backward-looking expectations • Rational expectations • Demand for labour and real wage rate • Expected inflation rate => increase in wage rate by inflation rate • Change in wage rate = output-gap effect + expectation effect
Recall, increases in other factor prices also shift AS upward • A negative AS shock • Not from labour cost • Actual inflation = • change-in-wage-rate inflation + supply-shock inflation = • output-gap inflation + expected inflation + supply-shock inflation • Let say, • No AD/AS shocks have happened for a while and none are expected • Then actual inflation = output-gap inflation + expected inflation + supply-shock inflation • Means: • Y = Y* • U = U* • Constant inflation • Liquidity preference theory: MD increases (P goes up), MS increases (the central bank adjusts) => interest rate stays constant
Shocks and inflation: • Positive AD shock • Demand inflation • No monetary validation • Factor prices adjust • P rises and then stops going up • Short-lived inflation • New price level but not new inflation rate • Monetary validation • Bank of Canada: • Sees an inflationary gap • Reduces interest rate • Money supply increases • AD increases • Get sustained inflation rate increase • Why would you do that?
Shocks and inflation: • Negative AS shock • Supply inflation • No monetary validation • Factor prices adjust • P rises and then falls and then stops changing • Short-lived inflation/deflation • Not new price level and not new inflation rate • Monetary validation • Bank of Canada: • Sees a recessionary gap • Reduces interest rate • Money supply increases • AD increases • Get short-lived inflation • Why would you do that? • Sticky wages
Shocks and inflation: • No monetary validation • Business cycle • No sustained inflation OR no inflation • Monetary validation • No business cycle • Sustained inflation OR new price level • Canada vs USA in early 1970s (OPEC) • Uh-oh! Monetary validation may give rise to a wage-price spiral • A shock => monetary validation => expectations adjusted upward => wages go up faster => inflation increases => (monetary validation) => expectations adjusted upward => wages go up faster => inflation increases => …
Shocks and inflation: • Again, positive AD shock • Monetary validation • Maintains Y > Y* • Adjusted expectations • Increased (accelerating) inflation rate • Means U < U* (NAIRU) • As long as there is inflationary gap there is accelerating inflation • No monetary validation • Allows return to Y > Y* • No change in expectations • Constant inflation rate • Means U = U* (NAIRU) • No sustained inflationary gap = no accelerating inflation • Sustained inflation comes from monetary validations • Sustained inflation is a monetary phenomenon • No increase in money supply, no sustained inflation
Disinflation: • Happened to many, historically • Sustained inflation is a monetary phenomenon • To disinflate, have to stop monetary validation • Phases: • Stop monetary validation • Interest rate up (Ms does not increase anymore) • Price level up • But only till Y=Y* • Stagflation • Negative AS shock due to established expectations • Will last till expectations adjust • Recovery • Reduced inflation expectation (AS down) • Expansionary policy may help but is DANGEROUS (why?)
Disinflation: • Phase 2 (stagflation) means reduced Y • Lost output = cost of disinflation • Sacrifice ratio = (cumulative loss of Y)/(% high inflation - % low inflation) • Speed of disinflation • Adjustment of expectations • In practice, usually significant political changes