A recent study by the U.S. Census Bureau shows that the population of Rock City Falls City, Illinois, is well spread out. About twenty-four percent of the population was under the age of 18, while six percent was 18 to 24 years old. Twenty-five percent were 25 to 44 years old, and twenty-four percent were 65 years of age and older. The median age of the population was forty-two years old, with males outnumbering females by a ratio of eighteen to one.
There are approximately 145 people living in Rock City, IL. The median property value in the city is $99,100, a number that is less than half the national average. Residents of Rock City, IL have a homeownership rate of 77.3%, which is slightly higher than the national average. Sixteen percent of people in Rock City, IL work in manufacturing. Twenty-seven percent of residents work in sales and related occupations.
The town's population grew following the arrival of the Atchison & Nebraska Railroad in 1871 and the Missouri Pacific Railroad in 1882. In 1909, it was designated a division point and reached a peak of six thousand citizens. Today, the town is home to U.S. Highway 73 and Nebraska Highway 8, which run west toward Salem, Nebraska and south along the state's southern border. Other state highways also connect the town to other smaller towns in Richardson County.