In a blog post, the company said while the market had been hit by the coronavirus pandemic, the worst of the declines was behind, as there would be smaller falls in the second, third and final quarters of 2020.
Canalys said the supply chain and manufacturing base in China had kicked off again and the need for hardware could be satisfied in sectors like remote working and education.
But this did not mean that the COVID-19 outbreak would not have a major recessionary impact, and companies would prioritise spending on other parts of their business rather than refreshing their PC and tablet stock.
“We expect this demand to persist, as many businesses that have been forced into home working and found it successful are now choosing to implement it on a larger scale.
"The same holds true for education, where schools have made investments in digital curricula and are implementing only partial returns to on-premises learning.
"Desktop refresh will suffer to a greater degree as businesses face prolonged uncertainty about the scope of their operations and dedicated office space needs.
"Tablets, which have the greatest reliance on consumer spending, will face a slump as holiday season demand in Q4 is expected to take a hit this year.”
Canalys claimed that the importance of PCs had been underlined during the pandemic.
“Canalys expects the global PC market to return to growth of 2% in 2022, with desktop and notebook shipments overcoming prolonged weakness in the tablet space," said Canalys research director Rushabh Doshi.
"But it is important to keep things in perspective: a modest recovery from a weak 2020 will not see the PC market return to the highs of 2019 for some years to come.”
Canalys has forecast differing declines in PC and tablets shipments for various regions: China will fall 3% this year and grow 4% in 2012; Asia-Pacific will fall 1% this and recovery will start in 2012; North America will fall 6% in 2020; Europe, the Middle East and Africa will fall 1%; and Latin America will fall about 8% in 2020.