Abraxas Petr. AXAS (RM) HighPoint Res. HPR (LR) Silverbow SBOW (RM) Apergy Corp. (APY) (MWM) Hornbeck Offsh HOS (DB) Smart Sand SND (MWM) Anadarko APC (CM) Independ. Cont. ICD (DB) Solaris Oilfield SOI (MWM) Apache APA (CM) Innospec Inc IOSP (RS) Southwestern SWN (CM) Archrock, Inc. AROC (DB) Key Energy Svcs. KEG (DB) SRC Energy SRCI (LR) Baker Hughes BHGE (DB) Kinder Morgan KMI (GV) Sundance SNDE (LR) Basic Energy BAS (DB) Kosmos Energy KOS (CM) Superior Engy SPN (DB) Berry Petrol. BRY (LR) Lilis Energy Inc. LLEX (RM) TEAM Inc. TISI (MWM) Cabot Oil COG (CM) Lonestar Res. LONE (RM) TechnipFMC plc FTI (MWM) Cactus, Inc. WHD (MWM) Magellan Midstr. MMP (GV) TETRA TTI (MWM) Callon Petl. CPE (RM) Magnolia Oil & Gas MGY (LR) Thermon Grp THR (MWM) Carrizo Oil CRZO (RM) Mammoth Energy TUSK (DB) Tidewater TDW (RS) Centennial Rs CDEV (LR) McDermott Intl. MDR (MWM) Transocean RIG (GV) Chaparral CHAP (RM) Montage Resrs. MR (RM) US Silica Hld SLCA (MWM) Chart Industr GTLS (MWM) Nabors Industries NBR (DB) U.S. WellSvcs USWS (DB) Chesapeake CHK (CM) National Oilwell NOV (MWM) Whiting Pet WLL (LR) C&J Energy CJ (DB) Newpark Res. NR (GV) WPX Energy WPX (LR) CNX Midstr. CNXM (GV) Noble Energy NBL (CM) Comstock CRK (RM) Noble Corp. NE (GV) Concho Res. CXO (CM) Noble Midstream NBLX (GV) Contango MCF (RM) Northern Oil NOG (LR) Continental Rs CLR (LR) Oasis Midstr. OMP (GV) Covia Holdings CVIA (MWM) Oasis Petroleum OAS (RM) Core Lab. CLB (GV) Oceaneering OII (DB) Denbury DNR (CM) Oil States Int'l OIS (DB) Devon DVN (CM) Parsley Energy PE (CM) Diamond Off DO (GV) Patterson-UTI PTEN (DB) Diamondback FANG (CM) PDC Energy PDCE (LR) Dril-Quip DRQ (MWM) Penn Virginia PVAC (LR) Earthstone ESTE (RM) Pioneer Energy PES (DB) Energen Corp EGN (CM) Pioneer Natural PXD (CM) Ensco plc ESV (GV) Plains All Amer PAA (GV) Enterprise Prod. EPD (GV) Propetro Hld. PUMP (DB) EOG Res. EOG (CM) QEP Resource QEP (LR) Evolution Pet EPM (LR) Quanta Srvs PWR (MWM) Flotek Industries FTK (GV) Range Res. RRC (RM) Forum Energy FET (MWM) Ranger Energy RNGR (DB) Gardner Denver GDI (RS) Rice Midstream RMP (GV) Goodrich Petr. GDP (RM) Ring Energy REI (RM) Gulf Island GIFI (MWM) Roan Res. ROAN (RM) Gulfport Energy GPOR (RM) Rowan RDC (GV) Halliburton HAL (DB) RPC Inc. RES (DB) Helix Energy HLX (MWM) Select Energy Svcs WTTR (MWM) Helmerich/Payne HP (DB) Sanchez Mid. SNMP (GV) Hi-Crush Partners HCR (MWM) Schlumberger SLB (DB) .