from Wikipedia, the free encyclopedia

Rate (from Latin rata pars 'calculated part' to ratum 'calculated' ) refers to a quantity related to a period of time. Colloquially, the term is sometimes used for a percentage, see quota .

  • a rate of change , i.e. the change in a variable over time (in the infinitesimal limit case the derivative of a variable)
  • Growth or decay rate as the rate of change of the logarithm of a size (equals the rate of change of the size in relation to the size itself)
  • a flow quantity as a qualitatively definable summand for the rate of change of a stock quantity (see also pro rata temporis )
  • Individual contributions to flows, in particular an installment payment
  • a flow variable related to another population size, such as the incidence rate (disease rate related to the population size)
  • Relationships of flow variables (or of their individual contributions), such as a freight rate

See also:

Wiktionary: Rate  - explanations of meanings, word origins, synonyms, translations