The Italian sparrow's breeding population is believed to comprise 5 to 10 million pairs, 750,000 to 900,000 of which are estimated to live in urban areas. It has a population density of 58 to 160 pairs per square kilometer. Up to the mid-1990s, its population increased steadily, probably due to increased urbanisation. Between 2000 and 2005, the Italian sparrow's population in Italy declined by 27.1 percent, mirroring the declines of the house sparrow throughout Europe. From 1998 to 2008, urban populations declined by about 50 percent. A study of the Italian sparrow's status listed a large number of potential causes for the Italian sparrow's decline, including shortages of insect food, agricultural intensification, and reductions of green areas. The Italian sparrow is among the most common birds in Italian cities, but other species, including the European goldfinch, are more common.