The total number of students who sat for the exam in 2019 also substantially declined from 2039 in 2018 to 1970 candidates last year.
The Ministry of Education revealed this trend while announcing the release of TSC results to schools.
A standard pass is English plus three best subjects at Achieved Grade.
The best performing school is Tonga High School with 86% pass rate. Tonga High School also had the most consistent improvement rate since 2016.
The most improved school from 2018 to 2019 was St. Joseph Community College with 31% pass rate, which is a 27% improvement from 2018.
The school with the most candidates enrolled in the TSC was Liahona High School with a total of 233 candidates.
Thirty schools offered the TSC exams in 2019.
Students can pick their results from the respective schools today (Tuesday).
The results of the candidates are shown by grades only.