As of the census of 2000, there were 213 people, 91 households, and 56 families residing in the township. The population density was 10.8 people per square mile. There were 142 housing units at an average density of 7.2/sq mi. The racial makeup of the township was 97.65% White, 0.47% African American, 0.94% Native American and 0.94% Asian. Hispanic or Latino of any race were 0.94% of the population. There were 91 households, out of which 26.4% had children under the age of 18 living with them, 44.0% were married couples living together, 11.0% had a female householder with no husband present, and 37.4% were non-families. 31.9% of all households were made up of individuals, and 18.7% had someone living alone who was 65 years of age or older. The average household size was 2.34 and the average family size was 2.93. In the township the population was spread out, with 19.2% under the age of 18, 8.0% from 18 to 24, 30.5% from 25 to 44, 24.9% from 45 to 64, and 17.4% who were 65 years of age or older. The median age was 40 years. For every 100 females there were 106.8 males. For every 100 females age 18 and over, there were 95.5 males. The median income for a household in the township was $28,250, and the median income for a family was $40,625. Males had a median income of $26,875 versus $20,417 for females. The per capita income for the township was $27,001. None of the families and 6.8% of the population were living below the poverty line, including no under eighteens and 2.6% of those over 64.
Brownlee - A village in the northern part of the township, about three miles northeast of Antrim.
Duncan - A village in the central part of the township, between Antrim and Brownlee.
Tioga State Forest - Much of eastern Duncan Township is covered by the Tioga State Forest.
Education
Residents of Duncan Township may attend the local, public schools operated by Wellsboro Area School District which provides full day kindergarten through 12th grade. In 2013, the District's enrollment declined to 1,526 students in kindergarten through 12th grade. In 2013, Wellsboro Area School District ranked 311th out of 498 public schools for academic achievement of its pupils, by the Pittsburgh Business Times. Duncan Township residents may also apply to attend any of the Commonwealth's 14 public cyber charter schools at no additional cost to the parents. The resident's public school district is required to pay the charter school and cyber charter school tuition for residents who attend these public schools. By Commonwealth law, if the District provides transportation for its own students, then the District must provide transportation to any school that lies within 10 miles of its borders. Residents may also seek admission for their school aged child to any other public school district. When accepted for admission, the student's parents are responsible for paying an annual tuition fee set by the Pennsylvania Department of Education. In 2012, the tuition fees for Wellsboro Area School District were: Elementary School – $8,343.38, High School - $9,951.51. BLaST Intermediate Unit #17 provides a wide variety of services to children living in its region which includes Duncan Township. Early screening, special educations services, speech and hearing therapy and many other services like driver education are available. Services for children during the preschool years are provided without cost to their families when the child is determined to meet eligibility requirements. Community members have access to the Green Free Library in Wellsboro; the Westfield Public Library which is located on Maple Street, in Westfield; the Mansfield public Library in Mansfield and to the statewide PA Power Library which is an online library funded with tax dollars from the state's education budget. Mansfield University of Pennsylvania is a state university located in Mansfield, Tioga County, Pennsylvania. Residents may take courses at a discounted tuition rate for state residents.
Government
The Township is governed by three locally elected Township Supervisors. ;County level: Three, elected at large, County Commissioners. ;State level:
