The Mac Observer reports that Apple’s US market share during January and March has jumped to 3.7% from 3.2% in the the previous quarter and from 2.6% in the year-ago quarter, according to a Gartner Dataquest study. Apple took the fifth position in terms of US market share, behind Dell, HP, Gateway, and IBM. Toshiba took the sixth spot.

UPDATE CNet now reports that IDC accidentally left out some Apple US shipments. The company’s US market share stands at 3.9%, according to IDC.