New York State Electric & Gas (NYSEG) lights up upstate New York. Organized in 1852, the company, a subsidiary of Avangrid (formerly known as Iberdrola USA) provides regulated energy services to more than 40% of upstate New York. The utility serves 872,000 electricity customers and about 256,000 natural gas customers in a 18,000 square mile area of central, eastern, and western New York. NYSEG operates more than 37,000 miles of power transmission and distribution lines and more than 440 substations; its transmission assets are overseen by the New York ISO. It owns 7,800 miles of gas distribution pipeline. The company also owns several hydroelectric power generation facilities.