propensity to save
in economics, the proportion of total income or of an increase in income that consumers save rather than spend on goods and services. The average propensity to save equals the ratio of total saving to total income; the marginal propensity to save equals the ratio of a change in saving to a change in income. The sum of the propensity to consume and the propensity to save always equals one (see propensity to consume).
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