More students in Northern Ireland have achieved grades A*-C this year.
The proportion has risen by 0.7 percentage points to 81.1%.
The number of entries achieving the A* grade is 9.9%, a small increase of 0.4 percentage points on the previous year, official results data showed.
The total of GCSE entries in Northern Ireland has decreased by 0.4% from 171,060 to 170,348.
There has been a slight improvement in GCSE English language and mathematics.
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— CCEA (@CCEA_info) August 23, 2018
STEM (Science, Technology, Engineering and Mathematics) subjects account for 43% of all GCSE entries in Northern Ireland, with an increase of 2.4% on the previous year.
Justin Edwards, chief executive of the Council for the Curriculum, Examinations and Assessment (CCEA), said: “There are some patterns worth further analysis, such as the continued widening of the performance gap at A*-C grades between males and females.”
The proportion of girls achieving A*-C grades increased to 85.1%, by 0.9 percentage points.
The proportion of entries by boys achieving A*-C grades rose by 0.5 percentage points to 76.9%.
The gap between girls and boys at A*-C grades has widened from 7.8 to 8.2 percentage points.
Mr Edwards added: “Subject choices remain stable with over 40% of students here now studying a STEM qualification. There were positive increases in further mathematics entries.”