As of the Census of 2010, there were 1,307,402 people living in the city of San Diego. That represents a population increase of just under 7% from the 1,223,400 people, 450,691 households, and 271,315 families reported in 2000. The estimated city population in 2009 was 1,306,300. The population density was 3,771.9 people per square mile (1,456.4/km2). The racial makeup of San Diego was 45.1% White, 6.7% African American, 0.6% Native American, 15.9% Asian (5.9% Filipino, 2.7% Chinese, 2.5% Vietnamese, 1.3% Indian, 1.0% Korean, 0.7% Japanese, 0.4% Laotian, 0.3% Cambodian, 0.1% Thai). 0.5% Pacific Islander (0.2% Guamanian, 0.1% Samoan, 0.1% Native Hawaiian), 12.3% from other races, and 5.1% from two or more races. The ethnic makeup of the city was 28.8% Hispanic or Latino (of any race); 24.9% of the total population were Mexican American, and 0.6% were Puerto Rican.

What was the population density of San Diego in 2009?