The difference between full employment level and equilibrium level of national income

The full employment level of national income represents the maximum output an economy can achieve when all resources, including labour, are fully utilised without causing excessive inflation. In contrast, the equilibrium level of national income occurs where total spending matches total output, but this may not always align with full employment.

Reasons for differences between full employment and equilibrium levels:

• Economic conditions - Economies seldom reach full employment because total spending (aggregate demand) can be either too high or too low compared to the output needed for maximum resource use.
• Spending imbalances - If aggregate expenditure exceeds the economy's potential output, it leads to inflationary pressures. Conversely, if spending is insufficient, output falls below potential, resulting in unemployment and unused resources.

The inflationary gap and its causes

An inflationary gap arises when the economy's total spending surpasses its potential output at full employment, creating excess demand that cannot be fully satisfied due to limited resources.

Characteristics and effects of the inflationary gap:

• Excess demand - With resources already fully employed, additional spending cannot increase output, leading to rising prices as firms compete for scarce inputs.
• Price level impact - The gap drives inflation, as businesses increase prices to manage the shortfall between demand and supply.
• Graphical representation - In a diagram, the inflationary gap is the vertical distance between the equilibrium gross domestic product (GDP) and the full employment output level, where equilibrium GDP exceeds full employment output.

Government responses to the inflationary gap

Governments can address an inflationary gap through fiscal policy measures aimed at reducing overall spending in the economy, thereby cooling demand and aligning it with potential output.

Key policy actions to close the inflationary gap:

• Reducing government spending - Cutting public expenditure on goods, services, or infrastructure decreases aggregate demand.
• Increasing taxation - Raising taxes reduces disposable income for households and businesses, leading to lower consumption and investment.
• Graphical impact - These measures shift the aggregate expenditure line downward in a diagram, moving the equilibrium GDP closer to the full employment level and narrowing the gap.

The deflationary gap and its causes

A deflationary gap occurs when the equilibrium level of GDP is below the full employment level, reflecting insufficient total spending to utilise all available resources.

Characteristics and effects of the deflationary gap:

• Insufficient aggregate expenditure - Low demand means firms produce less, leading to unemployment and spare capacity in the economy.
• Graphical representation - In a diagram, the deflationary gap is the vertical distance between the full employment output and the lower equilibrium GDP.

The Keynesian perspective on gaps and solutions

From a Keynesian viewpoint, economies may fail to reach full employment in the short run—or even the long run—due to inadequate demand, requiring active government intervention to stimulate activity.

Keynesian approach to the deflationary gap:

• Short-run and long-run challenges - Keynesians argue that without intervention, economies can remain stuck below full employment, as private sector spending alone may not suffice.
• Policy solution - To close a deflationary gap, governments should increase spending, often funded by borrowing, to boost aggregate demand.
• Graphical impact - This action shifts the aggregate expenditure line upward in a diagram, raising the equilibrium GDP toward the full employment level.

The aggregate expenditure formula

Aggregate expenditure represents the total spending in an economy, which determines the level of national income and output.

Formula for aggregate expenditure:

$\text{Aggregate expenditure}=C+I+G+(X-M)$

Where:

• C = Consumption (household spending on goods and services)
• I = Investment (business spending on capital goods)
• G = Government spending (public sector expenditure)
• X = Exports (goods and services sold abroad)
• M = Imports (goods and services bought from abroad)

The 45° line model for equilibrium national income

The 45° line model is a graphical tool used to illustrate how equilibrium national income is determined, based on the balance between total output and aggregate expenditure.

Features and applications of the 45° line model:

• Key elements - The 45° line represents points where aggregate expenditure equals output (national income). The aggregate expenditure curve plots total spending against income levels.
• Determining equilibrium - Equilibrium GDP is found at the intersection of the aggregate expenditure curve and the 45° line, where planned spending matches actual output.
• Analysing policy changes - Shifts in components like government spending move the aggregate expenditure curve, altering the equilibrium point. For example, increased government spending shifts the curve upward, raising equilibrium GDP.