The county's gains mirrored trends on the state level.
MERCER COUNTY -- High school graduation rates for most districts in the county continue to improve, with 11 out of 14 high schools showing gains.
The positive trend mirrored statewide data released Wednesday, which found that 89.7 percent of students who entered as ninth graders in the 2011-2012 school year graduated within four years.
All of the districts but Trenton and Ewing ranked above the state average.
Princeton High School reported the highest rate at 98.9 percent, followed by West Windsor-Plainsboro High School South at 98.6.
Three schools had declines: Ewing High School, Hopewell Valley Central High School and Trenton Central High School West.
But districtwide, Trenton's rate has improved over the last four years, which interim schools superintendent Lucy Feria had attributed to the stability of its programs and the commitment of its staff.
Find the rates for the schools below.
Cristina Rojas may be reached at crojas@njadvancemedia.com. Follow her on Twitter @CristinaRojasTT. Find The Times of Trenton on Facebook.