ruleyears

Ruleyears is a term used in the analysis of rules, policies, or governance mechanisms to describe the length of time a rule remains in effect. It represents the span between a rule’s enactment and its discontinuation or supersession, typically measured in years. In ongoing regimes, the current year may be used as the end date, yielding a partial-year calculation.

Usage in practice centers on regulatory analytics and knowledge engineering. In regulatory analytics, ruleyears help compare stability across rule sets, identify domains with frequent change, and estimate the burden of compliance. In rule-based systems or knowledge bases, ruleyears can be used to gauge rule durability, drive review schedules, or weight rules by their longevity.

Calculation methods vary. The basic form is ruleyears = end_year − start_year, with fractions for partial years when dates are known mid-year. When a rule has multiple revisions, a cumulative ruleyears can be obtained by summing the lifespans of each version or by treating each version as a separate rule with its own start and end.

Examples illustrate typical values. A rule enacted in 2000 and repealed in 2010 has 10 ruleyears. A rule introduced in 2015 and still active in 2024 has about 9 ruleyears (full-year counting) or 9.5 if partial years are included.

Variants and related concepts include rule lifetime, policy duration, and validity period. See also data provenance, version control, and governance analytics.