The sister city of Waverly is the German city of Eisenach, which is famous for the Wartburg castle. Waverly is also the home of Wartburg College which is named after this castle.
As of the census of 2000, there were 8,968 people, 3,238 households, and 2,143 families residing in the city. The population density was 803.4 people per square mile (310.3/km²). There were 3,394 housing units at an average density of 304.0/sq mi (117.4/km²). The racial makeup of the city was 97.11% White, 1.05% African American, 0.11% Native American, 0.87% Asian, 0.01% Pacific Islander, 0.12% from other races, and 0.72% from two or more races. Hispanic or Latino of any race were 0.61% of the population.
There were 3,238 households out of which 30.6% had children under the age of 18 living with them, 57.1% were married couples living together, 6.8% had a female householder with no husband present, and 33.8% were non-families. 28.4% of all households were made up of individuals and 13.7% had someone living alone who was 65 years of age or older. The average household size was 2.36 and the average family size was 2.90.
In the city the population was spread out with 21.5% under the age of 18, 20.4% from 18 to 24, 21.5% from 25 to 44, 20.3% from 16.3% who were 65 years of age or older. The median age was 34 years. For every 100 females there were 88.2 males. For every 100 females age 18 and over, there were 82.4 males.
The median income for a household in the city was $39,587, and the median income for a family was $52,656. Males had a median income of $36,369 versus $22,031 for females. The per capita income for the city was $18,285. About 2.1% of families and 6.3% of the population were below the poverty line, including 2.0% of those under age 18 and 5.8% of those age 65 or over.