Indigenous peoples of Mexico (Spanish: pueblos indigenas de Mexico), Native Mexicans (Spanish: nativos mexicanos), or Mexican Native Americans (Spanish: nativo america mexicanos), are those who are part of communities that trace their roots back to populations and communities that existed in what is now Mexico prior to the arrival of Europeans. According to the National Commission for the Development of Indigenous Peoples (Comision Nacional para el Desarrollo de los Pueblos Indigenas, or CDI in Spanish) and the INEGI (official census institute), in 2015, 25,694,928 people in Mexico self-identify as being indigenous of many different ethnic groups, which constitute 21.5% of Mexico's population.

According to the National Commission for the Development of the Indigenous Peoples (CDI), there were 25,694,928 indigenous people reported in Mexico in 2015, which constitutes 21.5% of the population of Mexico. This is a significant increase from the 2010 census, in which indigenous Mexicans accounted for 14.9% of the population, and numbered 15,700,000 Most indigenous communities have a degree of financial, political autonomy under the legislation of "usos y costumbres", which allows them to regulate internal issues under customary law.  The indigenous population of Mexico has in recent decades increased both in absolute numbers as-well as a percentage of the population. This is largely due to increased self-identification as indigenous, as-well as indigenous women having higher birth rates as compared to the Mexican average. Indigenous peoples are more likely to live in more rural areas, than the Mexican average, but many do reside in urban or suburban areas, particularly, in the central states of Mexico, Puebla, Tlaxcala, the Federal District and the Yucatan Peninsula.  According to the CDI, the states with the greatest percentage of indigenous population are: Yucatan, with 65.40%, Quintana Roo with 44.44% and Campeche with 44.54% of the population being indigenous, most of them Maya; Oaxaca with 65.73% of the population, the most numerous groups being the Mixtec and Zapotec peoples; Chiapas has 36.15%, the majority being Tzeltal and Tzotzil Maya; Hidalgo with 36.21%, the majority being Otomi; Puebla with 35.28%, and Guerrero with 33.92%, mostly Nahua people and the states of San Luis Potosi and Veracruz both home to a population of 19% indigenous people, mostly from the Totonac, Nahua and Teenek (Huastec) groups.

Using a quote from the above article, answer the following question: How many different groups of indigenous peoples are included in those statistics?
Totonac, Nahua and Teenek (Huastec) groups.