query: When was the Institutional Revolutionary Party established in Mexico?
passage: Institutional Revolutionary Party
The Institutional Revolutionary Party (Spanish: Partido Revolucionario Institucional, PRI) is a Mexican political party founded in 1929 that held uninterrupted power in the country for 71 years from 1929 to 2000, first as the National Revolutionary Party (Spanish: Partido Nacional Revolucionario, PNR), then as the Party of the Mexican Revolution (Spanish: Partido de la Revolución Mexicana, PRM), and finally renaming itself as the Institutional Revolutionary Party in 1946.
passage: Institutional Revolutionary Party
The adherents of the PRI party are known in Mexico as "Priístas" and the party is nicknamed "El tricolor" (The tricolor) because of its use of the Mexican national colors of green, white and red, as found on the Mexican flag.