Worldwide shipments of personal computers fell 11% in the three months from April to June, according to data from research firms Gartner and IDC, as people continued to migrate to tablets and other mobile devices.

Gartner said that the PC industry is now experiencing the longest decline in its history, as shipments dropped for the fifth consecutive quarter.

Computer makers shipped 76 million PCs in the April-June period, down from 85 million in the same three months of 2012, its figures show.

International Data Corp., which uses slightly different methodology, essentially came to the same conclusion, though it noted that the decline was slightly smaller than expected.

"With second quarter growth so close to forecast, we are still looking for some improvement in growth during the second half of the year," IDC said in a statement. "Slower growth in Europe and China reflect the risks, while the improved US outlook reflects potential improvement,'' it added.

Gartner said inexpensive tablets are displacing low-end computers in "mature" markets such as the US.

In emerging markets like China, meanwhile "inexpensive tablets have become the first computing device for many people, who at best are deferring the purchase of a PC. This is also accounting for the collapse of the mini notebook market," it added.

IDC said the numbers "reflect a market that is still struggling with the transition to touch-based systems running Windows 8." Microsoft's latest operating system launched in October, and sales have disappointed analysts.

IDC said that while "Windows 8 has been blamed by some as the reason for the PC market's decline, we believe this is unfounded as it does not explain the sustained decline in PC shipments."

Lenovo was the number one PC maker, beating out rival Hewlett-Packard by a narrow margin, according to both firms.