Until the 1980s, the government sponsored the teaching of Nepali in schools in southern Bhutan. With the adoption of the "Driglam Namzhag" (Bhutanese code of etiquette) and its expansion into the idea of strengthening the role of Dzongkha, Nepali was dropped from the curriculum. The languages of Bhutan are still not well characterized, and several have yet to be recorded in an in-depth academic grammar. Before the 1980s, the Lhotshampa (Nepali-speaking community), mainly based in southern Bhutan, constituted approximately 30% of the population. However, after a purge of Lhotshaampas from 1990 to 1992 this number might not accurately reflect the current population.