The number of active U.S. drilling rigs fell for a second consecutive week, according to Baker Hughes. The closely watched tally showed the total rig count declined by eight to 539 in the week ended July 3, with oil-directed rigs down seven to 425 and natural-gas rigs slipping by one to 108. Activity in the Permian Basin, the country’s most prolific shale field, accounted for much of the pull-back as oil rigs there fell by five to 263. The latest figures suggest producers are trimming spending amid softer crude prices, after oil futures slipped below $67 a barrel on Friday.