Parity Index Law and Legal Definition
The "parity index," as of any date, shall be the ratio of (i) the " general level of prices for articles and services that farmers buy, wages paid hired farm labor, interest on farm indebtedness secured by farm real estate, and taxes on farm real estate, for the calendar month ending last before such date to (ii) the general level of such prices, wages, rates, and taxes during the period January 1910 to December 1914, inclusive.” (7 USCS § 1301)