Definition: Cyclical component of a time series
OECD - Data and Metadata Reporting
The cyclical component of a time series refers to (regular or periodic) fluctuations around the trend, excluding the irregular component, revealing a succession of phases of expansion and contraction.
The cyclical component can be viewed as those fluctuations in a time series which are longer than a given threshold, e.g. 1.5 years, but shorter than those attributed to the trend.
Task force on data and metadata presentation for the OECD Short-term Economic Statistics Working Party (STESWP), Paris, 2004 [quoted in Organisation for Economic Co-operation and Development (OECD), "Data and Metadata Reporting and Presentation Handbook", OECD, Paris, 2007]