Marginal propensity to import

The marginal propensity to import (MPM) is the fractional change in import expenditure that occurs with a change in GDP.

Mathematically, the marginal propensity to import (MPM) function is expressed as the ratio of the import (M) function with respect to GDP (Y).

$\mathrm {MPM} ={\frac {{\text{Δ}}M}{{\text{Δ}}Y}}$

In other words, the marginal propensity to import is measured as the ratio of the change in imports to the change in GDP, thus giving us a figure between 0 and 1.

See also

• Marginal propensity to save
• Marginal propensity to consume
• Automatic stabiliser
• Multiplier model

Further reading

• Shinohara, Miyohei (1957). "The Multiplier and the Marginal Propensity to Import". American Economic Review. 47 (5): 608–624. JSTOR 1811740.