SLOPE, NET EXPORTS LINE: The negative slope of the net exports line is based on the marginal propensity to import (MPM). Because net exports are exports minus imports, the induced change in imports causes an opposite change in net exports. As such, the slope of the net exports line is negative, less than zero (but greater than negative one). The slope of the net exports line affects the slope of the aggregate expenditures line and thus also affects the magnitude of the multiplier process.
A representative net exports line is presented in the exhibit to the right. This red line, labeled X-M in the exhibit, is negatively sloped, indicating that greater levels of income or production generate smaller levels of net exports by the foreign sector. This negative relation indicates that imports, which are subtracted from exports to derived net exports, are induced by an expanding economy. The net exports line graphically illustrates the net exports-income relation for the foreign sector, which is then added to the consumption line to derive the aggregate expenditures line used in Keynesian economics to identify equilibrium income and production. The slope of the net exports line presented here is negative. In fact, the slope of the net exports line is numerically equal to the negative of the marginal propensity to import. In this case the slope is equal to -0.075. The negative slope reflects induced net exports--more income means fewer net exports. Click the [Slope] button to illustrate. To illustrate the equality between slope and the negative of the marginal propensity to import, consider the equations for each. The slope of the net exports line is specified as the "rise" over the "run." The rise is the change in net exports measured on the vertical axis and the run is the change in income measured on the horizontal axis. However, because exports are autonomous, the only income induced change in net exports comes from imports, in a negative way. The marginal propensity to import (MPM) is the incremental change in net exports resulting from an incremental change in income. The negative slope of the net exports line is the marginal propensity to import, or the slope of the net exports line is the negative of the marginal propensity to import, on is the negative of the other. The negative slope of the net exports line reflects induced net exports, which is net exports that depend on the level of income. If the aggregate economy has more income, then the foreign sector is induced to undertake fewer net exports. Of course, a drop in aggregate income induces the foreign sector to increase net exports. Check Out These Related Terms... | net exports line | intercept, net exports line | consumption line | slope, consumption line | slope, investment line | slope, net exports line | induced net exports | autonomous net exports | marginal propensity to import | Or For A Little Background... | net exports | exports | imports | net exports of goods and services | Keynesian economics | macroeconomics | foreign sector | national income | gross domestic product | determinants | And For Further Study... | induced expenditures | autonomous expenditures | aggregate expenditures | aggregate expenditures line | derivation, consumption line | net exports determinants | Keynesian model | Keynesian equilibrium | injections | leakages | injections-leakages model | aggregate demand | paradox of thrift | fiscal policy | multiplier | Recommended Citation: SLOPE, NET EXPORTS LINE, AmosWEB Encyclonomic WEB*pedia, http://www.AmosWEB.com, AmosWEB LLC, 2000-2025. [Accessed: December 16, 2025]. |
