May 22, 2003 Inflation targeting, a stable macroeconomic environment, and an average growth rate for potential output that is not expected to vary much in the next several years all help households, businesses, and governments in their medium-term economic and financial planning. Several simple rules of thumb can be usefully employed in this planning. Specifically, inflation targeting has maintained most major measures of inflation quite close to the target midpoint on average over a number of years. Combined with a clear fiscal framework, this has contributed to a more stable macroeconomic environment in which output varies less around its potential level. Potential output growth is expected to average around 3 per cent over the next several years. In light of these factors and historical relationships, labour income, profits, and consumer spending will likely grow, on average, by about 5 per cent over the medium term. Real and nominal long-term interest rates should also continue to be stable, with real 30-year yields varying around 3.5 or 4.0 per cent, and nominal yields varying around 5.5 or 6.0 per cent.
Traditional structural models cannot distinguish whether changes in activity are a function of altered expectations today or lagged responses to past plans. Polynomial-adjustment-cost (PAC) models remove this ambiguity by explicitly separating observed dynamic behaviour into movements that have been induced by changes in expectations, and responses to expectations, that have been delayed because of adjustment costs.