John Wood Group plc has cut its workforce by 36 percent over a two year period, the oilfield services company revealed Tuesday.  “Following a sustainable overhead cost reduction of $148 million in 2015, we reduced overhead costs by a further $96 million in 2016,” Wood Group Chief Executive Robin Watson said in a statement.  “This has meant further tough decisions which directly impact our people. Underlying headcount, excluding acquisitions, is down 36 percent over a two year period,” he added.  Watson, who believes the savings achieved are sustainable into 2017, suggested that the market environment will remain tough for the company for the rest of the year.  “Overall, the oil and gas market continues to present challenges in 2017,” he said.  “We anticipate modest recovery only in markets such as U.S. onshore and greenfield offshore projects,” he added.  Wood Group CFO David Kemp said in December 2016 that the company showed modest recovery in its U.S. shale and offshore oil exploration and drilling businesses.