Crude oil prices edge lower as doubts persist over whether the OPEC-led effort to keep markets in balance has any durability. File photo by Monika Graff/UPI July 5 (UPI) — Pessimism over the appetite of some major oil producers to work hard to balance the market with deeper cuts pushed oil prices lower in early Wednesday trading. Crude oil prices entered July in the midst of one of the stronger surges in five years after reports last week showed a decline in U.S. crude oil production and a move backward for North American rig counts. U.S. shale oil production has proven more resilient to lower crude oil prices than initially expected, though oil prices touched historic lows in June and suppressed some of the appetite for spending in the American oil market. Higher U.S. output, coupled with the previous OPEC policy to defend a market share with production growth, […]