Fünfjahres

Fünfjahres is a German combining form used to denote a period of five years. It is a bound morpheme that typically attaches to a following noun to form a compound word, such as Fünfjahresplan, Fünfjahreszeitraum or Fünfjahresperiode. In standard orthography the form is often written with a hyphen (Fünfjahres-) when it serves as a prefix, but many compounds are closed as a single word (Fünfjahresplan).

The term is primarily found in formal, administrative, or historical writing. It designates a time span of five calendar years rather than a single year. The most well-known use is in the phrase Fünfjahresplan, the German translation of "five-year plan," historically associated with planned economies in the 20th century, including the Soviet model and the East German planning system. Beyond political contexts, Fünfjahres is used to describe non-political five-year time frames, such as a project's budget cycle or a research program running over a five-year period.

Etymology: Fünf is the cardinal number five and Jahre is the plural of Jahr (year); the -s ending links the elements in a compound form. The construction is similar to other time-span prefixes such as Vierjahres- (four-year).

See also: Fünfjahresplan, Planwirtschaft, Zeitspanne, Zeitraum.