Parliament adjourned this week, ending a sitting that has taken a toll on Justin Trudeau's approval ratings.

Though a majority of Canadians still approve of the job he is doing as prime minister, that share has decreased significantly since his government approached its first summer recess around this time one year ago.

According to the CBC's Leader Meter, which tracks the approval ratings of each of the party leaders in the House of Commons, Trudeau has averaged a 52.7 per cent approval rate in the three most recent polls, with 39.3 per cent disapproving of his performance.

In the three polls conducted just before the House adjourned in June 2016, Trudeau averaged an approval rating of 61.7 per cent, with disapproval at 32.7 per cent.

This shift is in contrast to the impact of his government's first year in office.

In the first three polls conducted after Trudeau became prime minister, he averaged 60 per cent approval — suggesting his approval rating actually went up slightly after the fall 2015/spring 2016 parliamentary sitting.

By comparison, Trudeau's approval rating has slipped nine points over the last year, while his disapproval rating has increased by 6.6 points.

Nevertheless, Trudeau is still the most popular government leader in the country. Polls by Mainstreet Research and the Angus Reid Institute (ARI) show that Trudeau boasts a higher approval rating nationwide than any premier does within her or his own province.

Trudeau's declining approval ratings have been a consistent trend over the last year — and one that has been recorded by every pollster that has been in the field over that time.

Polls by Mainstreet, ARI and Forum Research have all recorded a nine to 10 point drop in Trudeau's approval rating, with his disapproval rating increasing by eight to 11 points between June 2016 and June 2017:

Trudeau takes a hit where he's most popular

Regional data from the Forum and ARI polls suggest that where Trudeau is the most popular is also where his support has declined most steeply.

Across these two polls, Trudeau's approval rating has dropped 13 points in Atlantic Canada, 10.5 points in B.C. and 9.5 points in Quebec.

But these three regions are where Trudeau's net approval ratings (approval minus disapproval) are still highest: +11.5 in B.C., +26 in Quebec and +28.5 in Atlantic Canada.

Trudeau also remains more popular than his party, which is polling around 40 per cent support among decided voters.

This is partly because of his approval ratings among New Democrat supporters. While just 11 to 18 per cent of Conservative voters say they approve of Trudeau, according to Campaign and Forum polls, that increases to 37 to 48 per cent among NDP voters.

Scheer unknown to half of Canadians

Polls suggest about half of Canadians do not have an opinion of the new Conservative leader.

Andrew Scheer has averaged an approval rating of 26 per cent over the three polls conducted since he took over the party's top job, compared to a 23.7 per cent disapproval rating. That leaves an average of just over 50 per cent of respondents who said they were unsure of what they thought of Scheer.

Half of Canadians have no opinion of new Conservative Leader Andrew Scheer. (Justin Tang/Canadian Press)

That compares poorly to the leaders of the two other recognized parties in the House of Commons. Roughly 70 per cent of Canadians had an opinion of Trudeau and Tom Mulcair when they became the leaders of their respective parties.

Mulcair, who will step down as leader of the NDP after the party chooses his replacement in October, has not seen significant movement in his approval ratings over the last year. The share of Canadians who say they disapprove of his performance, however, has fallen by 11 points.

Like Scheer, the next NDP leader will probably be largely unknown. A recent Campaign poll found that 80 per cent of Canadians had no opinion who, among the five candidates currently in the running, would be the best person to lead the party.

But by the time the next federal election rolls around in 2019, Trudeau won't be able to count on his two opponents being so unknown to the general public. And while the numbers do not yet suggest the Liberals should panic, if his approval ratings continue to take a hit with each passing season, he won't be able to count on being more popular than his rivals.