Driven by an increase in immigration to record levels, Canada’s population surged by 1.2% over the past year, Statistics Canada announced on Wednesday.

According to preliminary estimates, Canada’s population was 36.3 million as of July 1, StatsCan says. This represents an increase of 437,815 during the year, which is the highest population increase since 1988/1989, when the population grew by 485,034.

“This acceleration in population growth was mainly attributable to the record number of immigrants (320,932) who arrived in the country,” says the national statistical agency in a news release. “The arrival of Syrian refugees since November 2015 contributed to the increase in immigration in Canada.”

The previous record for immigration was set in 2009/2010, when 270,581 people migrated to Canada. “The country had not received such a large number of immigrants in a single annual period since the early 1910s during the settlement of Western Canada,” StatsCan adds.

The population also continues to age, StatsCan reports, with the average age rising 0.1 years to 40.6 years old. The proportion of those aged 65 and older also rose by 0.4 percentage points to 16.5% of the total population.