"most severe yearly contraction on record" for the industry, worse than the 9.7% estimate.
The last six quarters have seen drops, the longest historically, with global shipments affected by mobile and tablet devices. There's "little indication of positive growth" beyond replacements.
IDC had hoped to see improvement for the second half of the year but revised down their numbers. Replacement of older PCs remains the strong force behind sales.
"Perhaps the chief concern for future PC demand is a lack of reasons to replace an older system," Jay Chou, Senior Research Analyst, Worldwide Quarterly PC Trackers at IDC. "While IDC research finds that the PC still remains the primary computing device – for example, PCs are used more hours per day than tablets or phones – PC usage is nonetheless declining each year as more devices become available."
"And despite industry efforts, PC usage has not moved significantly beyond consumption and productivity tasks to differentiate PCs from other devices. As a result, PC lifespans continue to increase, thereby limiting market growth."
Shipments will likely see decline in 2014 too, although not as severe. The trouble has been the mobile and tablet devices grabbing hold of first-time consumers, making it difficult for PC to expand. Thecontinued saying commercial shipments would fall 5% in 2013, and 15% among consumers.
Commercial was better because of a "mix of more stable PC investment planning, a smaller impact from tablets, and to replacements of Windows XP systems before the end of support planned for 2014," said the IDC.
"However, the long-term outlook for the two markets is not significantly different, with a small decline projected for both consumer and commercial segments in 2014 with near flat growth in the longer term."
Can Valve ride to the rescue with their Steam Machines? Could they inject much needed new consumer blood?