Full employment level of national income
This is a really important conceptNational Income (Y) can be calculated by measuring the total level of output of the economy (GDP etc).
Generally speaking, the more the economy produces, the more
people (Labour) will be needed to produce extra goods and services.
However, there will be a maximum level of output
where everyone (and land and capital) available is employed and no more
output can be produced. You can think of this as the economy being at
its full capacity - all factors of production being used efficiently.
This level of output is called the full employment level of national income. At this level of income, there is no shortage of demand in the economy and therefore there is no Cyclical Unemployment - but there may still be Structural and Frictional Unemployment.
NB This level of GDP is also referred to as - the Natural Rate of Unemployment by neoclassicists and Non Accelerating Inflation, Rate of Unemployment (NAIRU) by Keynesians.
You can see the level of full employment income in Figure 1 below -
Yfe. It is the reason why the Keynesian LRAS has a vertical section and
is the level opf GDP that positions the neoclassical LRAS.