At the same time, the total shipments of tablets dropped by over 1.5% from those of the first quarter.
IDC research said however, they believe the tablet market will have a positive but slower rate of growth during 2014 in comparison to 2013.
Apple maintained its top spot in the market, but Lenovo, Asus and rival Samsung slowly are taking more share of the market.
Shipments of Apple tablets were 13.3 million, which were lower by 9.3% compared to last year. The share of the market owned by Apple is just under 27%.
The market for tablets is in a new phase, said one analyst, with smaller vendors leveling off the playing field as well as the market share.
Apple as well as analysts attributed the decline in iPad sales to markets that remain economically weak and slow new purchases by users, who have stayed with one device for periods that are longer than expected.
IBM and Apple last week entered into a deal to sell jointly the iPad and iPhone to large companies. The tablet offering that are enterprise specific could boost sales of the iPad during the second six months of 2014, said one research analyst.
The biggest threat to Apple is Samsung, whose sales of tablets were 8.5 million in the second quarter, which increased its share of the tablet market by 1.6% compared to the same period one year ago.
Lenovo, the third place finisher, increased its year over year by more than 64% to over 2.4 million units. Those figures helped the China based company to overtake Asustek, which dropped to fourth with 2.3 million tablets shipped. Fifth place, on the list, was held down by Acer whose total shipments fell by 36%.