In macroeconomics '''automatic stabilisers''' work as a tool to dampen fluctuations in real GDP without any explicit policy action by the government. 

The size of the government multiplier. 

Furthermore, imports often tend to decrease in a recession, meaning more of the national income is spent at home rather than abroad. This also helps stabilise the economy.

==Induced taxes==
Government tax revenue tends to fall as a proportion of national income during recessions.

This occurs because of the way tax systems are generally constructed.
*progressive. If an individual's income rises, then their average tax rate increases. This means that as incomes fall, households pay less as a proportion of their income in direct taxation.
*turnover. In a recession profits tend to fall much faster than turnover. Therefore, a corporation pays much less tax while  having only slightly less economic activity.

If national income rises, by contrast, then both households and corporations end up paying higher proportions of their income in tax. 

This means that in an economic boom tax revenue is higher and in a recession tax revenue lower; not only in absolute terms but as a proportion of national income. 

Other forms of tax do not exhibit these effects, because they are roughly proportionate to income (e.g. taxes on consumption like sales tax or value added tax, or they bear no relation to income (e.g. poll tax or property tax). 

===Transfer payments===
Most governments also pay welfare benefits. Generally speaking, the number of unemployed people and those on low incomes who are entitled to other benefits increases in a recession and decreases in a boom.

This means that ''government expenditure increases automatically in recessions and decreases automatically in a boom'' in absolute terms. Since the trend of output is to increase in booms and decrease in recessions, expenditure is expected to increase as a share of income in recessions and decrease as a share of income in booms.

==Imports==
Generally, as the income of an individual or an entire economy increases the greater the marginal propensity to import; the more income you earn the more likely you are to purchase imported goods. 

Imports have the effect of lessening the amount of money into a local economy as money is exchanged for goods and services originating from an international source. Again, as the income of the economy increases the greater the amount of money being lost to international economies through imports, while times of recession tend to keep imports low, keeping more money in the domestic economy. 

Recessions and booms are, however, often accompanied by currency fluctuations which significantly change import and export behaviour.

==When stabilisers don't work==
There is broad consensus amongst economists that the automatic stabilisers often exist and function in the short term. 

However, the automatic stabilisers model does not incorporate rational expectations or other microfoundations. No part of economics is in the final analysis a mechanistic process and the existence of the stabilisers can easily be overshadowed by other changes to policy, expectations or markets. 

'''Automatische Stabilisatoren''' sind fiskalpolitische Mechanismen, die bei konjunkturellen Schwankungen automatisch dafür sorgen, dass die gesamtwirtschaftliche Nachfrage stabilisiert wird. 

Ihre Wirkung beruht darauf, dass sowohl Teile der staatlichen Einnahmen als auch der Ausgaben mit der Konjunktur schwanken. 
Einerseits gehen die Steuereinnahmen bei einer konjunkturellen Abschwächung in der Tendenz zurück (oder sie wachsen zumindest langsamer), andererseits muss der Staat mehr für soziale Leistungen aufwenden. Dadurch entsteht im Staatshaushalt ein Defizit (oder ein vorher vorhandener Überschuss wird kleiner). 

In Konjunkturaufschwüngen verläuft die Wirkung umgekehrt: Ausgaben für Sozialleistungen sinken und die Steuereinnahmen steigen, ein Defizit im Staatshaushalt wird abgebaut oder es entstehen Überschüsse. Dadurch dämpft der Staat im Aufschwung die Konjunktur. Insgesamt verstetigen automatische Stabilisatoren das Wirtschaftswachstum, Abschwünge werden gemildert und Aufschwünge gedämpft.