PNM serves about 550,000 electricity customers throughout New Mexico. The company, New Mexico's largest electricity provider, is based in Albuquerque. PNM was founded in 1917 as the Albuquerque Gas and Electric Co. and has undergone several transformations, including name changes, in its history. It sold its natural gas utility to New Mexico Gas Company in 2009. The PNM Resources Foundation, a non-profit, tax-exempt corporation, has established generous contributions to non-profit organizations and educators in New Mexico. PNM is one of two subsidiaries of TXNM Energy, an investor-owned energy holding company also based in Albuquerque.