ranges from 10–11 hours of sunshine/day in January to about 5 hours of sunshine/day (less cloudier areas) to less than 3 hours of sunshine/day (more cloudier areas) in July. Demographics According to the results from the , the province has a population of 638,645 with 316,774 males and 321,871 females. It constitutes 1.6% of the total population in Argentina. This represented a 15.5% increase in the population compared to which had 552,822 inhabitants. Amongst of all the provinces in Patagonia, it is the most populous, containing 30.4% of the total population in Patagonia. The province is home to four indigenous groups: The Tehuelches, the Puelches, the Pehuenches, and the Mapuches. Almost all of the indigenous population in the province are the Mapuches with the rest being small in number where their few descendants live in the neighbouring provinces. The Mapuches along with some of the Pehuenches originally lived in the western parts of the province although today, they mainly live in the southern parts of the province. The Tehuelches were nomadic people that hunted on the steppes in the province. The Puelches, being also nomadic, lived on the northern margins of Nahuel Huapi Lake and the surrounding forests in the Andean mountains, living off hunting and fishing. It is estimated that Mapuches started coming to the region before 1880 from Chile, leading to the imposition of their culture onto the other indigenous groups. Originally agricultural people, the Mapuches became nomadic upon arrival to the province due to the utilization of horses. The province received immigrants mostly from Chile, Italy, Spain, Germany and the United Kingdom during the last years of the 19th century and the first years of the 20th century. Government The provincial government is divided into the usual three branches: the executive, headed by a popularly elected governor, who appoints the cabinet; the legislative; and the judiciary, headed by the Supreme Court. As of December 2019, Arabela Carreras became governor of the province, following the retirement of Alberto Weretilneck due to term-limit. She is the first woman elected governor of the province. The Constitution of Río Negro Province forms the formal law of the province. In Argentina, the most important law enforcement organization is the Argentine Federal Police but the additional work is carried out by the Río Negro Provincial Police. Political division The province is divided into 13 departments: Department (Capital) Adolfo Alsina Department (Viedma) Avellaneda Department