Quebec's public schools have a lower graduation rate than other provinces in Canada, according to a study released Wednesday.

This even as Quebec's high school students are posting the best math scores in the country.

The Institut du Quebec looked at the five-year graduation rate, or how many children successfully finish high school five years after they begin.

It showed that overall, 64 percent of Quebec public school students finish on time.

The graduation rate is much better in Quebec's private schools which are attended by about 20 percent of students in the province -- a higher percentage than anywhere else in Canada.

But even when the graduation rate from private schools is included Quebec's overall graduation rate is 69 percent, which is still the lowest of any province.

There is also a significant difference among English school boards and French school boards. More than 76 percent of students at English school boards graduate within five years.

About 85 percent of students in Ontario, Nova Scotia, and New Brunswick finish high school on time.

The five-year graduation rate for boys is even worse: only half of boys graduate high school in Quebec within five years of starting.

While Quebec students may not succeed within five years most people eventually finish high school, with more than 80 percent of students graduating within seven years of starting, and 89 percent of people aged 25 to 34 having a high school degree.

The Institute's report noted that funding for schools in Quebec and Ontario has increased over the past decade, but while Ontario's graduation rate has improved, Quebec's has not.

The number of dropouts in Quebec has been steadily decreasing this century. In 1999-2000 about 22  percent of students were dropouts, while that number is now 13 percent.

A report released earlier this week by the Council of Ministers of Education Canada showed that students in French public schools in Quebec were the best in the country in mathematics, and that girls had better reading comprehension than boys in every province.