These numbers are composite numbers from Seagate and Western Digital and include Hitachi GST (and IBM before that companies HDD business became part of Hitachi GST) until 2009 when HGST quit publically reporting their ASPs.

FORBES: Why Government Regulators Should Approve Hard Disk Drive Company Consolidation

Other competitors in the energy sector include: Gastar Exploration Limited (USA) (GST), Devon Energy (DVN), and EOG Resources (EOG).

FORBES: Earnings Preview: Chesapeake Energy