Groeigap

Groeigap is a macroeconomic concept used to quantify the lag between an economy’s potential growth path and its actual growth path over a given period. The term blends growth and gap and has appeared in theoretical and empirical macroeconomic literature as a way to capture the pace of adjustment after disturbances.

Definition and calculation: Groeigap can be defined as the time-weighted difference between potential GDP growth and realized GDP growth across a business cycle, often normalized by the cycle’s duration. A simple representation is groeigap = (1/T) ∫_0^T [g_pot(t) − g_act(t)] dt, where g_pot is the growth rate of potential GDP and g_act is the observed growth rate. Because potential growth is not directly observable, economists estimate it using trend components from filters or production-function approaches, while actual growth derives from official GDP data.

Interpretation and use: A positive groeigap indicates that actual growth was, on average, below potential during the period, signaling slack, slower adjustment, or structural constraints. A negative groeigap suggests above-potential performance on average. The metric is used to compare recoveries after shocks, assess policy timing and effectiveness, and examine differences across regions or sectors. It is often employed in model testing to understand frictions or lags in adjustment processes.

Limitations: Groeigap relies on methods for estimating potential growth and the choice of cycle length, both of which introduce uncertainty. Different estimation techniques can yield different groeigap values, complicating cross-study comparisons. Despite these caveats, groeigap offers a compact way to summarize the pace at which an economy closes the gap between actual and potential growth. See also: output gap, growth accounting, business cycle.