Mathematics is essential to life as everyone uses mathematical concepts daily. Many countries have advanced in science and technology by investing in mathematics. This study aimed to determine the trend of students who sat for the Certificate of Secondary Education Examination (CSEE) in mathematics from 2015 to 2022; analyse performance trends in mathematics during this period, examine mathematics failure rate trends, and project pass rates in mathematics for the next eight years, from 2023 to 2030. This study employed a quantitative research approach and an ex-post facto research design. Participants were 4,459,009 students who sat for CSEE from 2015–2022. Analysis from the Statistical Package for Social Sciences version 26.0 revealed a consistent rise in student enrollment, with 136,481 more students by 2022. The pass rate was low, as the maximum was 20.12%, while failure rates consistently exceeded 78%. The findings indicated further that the pass rates would remain low from 2023 to 2030. The study recommends reviewing secondary school mathematics curriculum, increasing teaching and learning materials, providing regular in-service training in innovative pedagogical practices and assessment, and hiring more mathematics teachers in secondary schools.