| PACX | Pacific Supply Cooperative | added 10/74; 1/75; eliminated 1/78 |
| Plasser American Corp. | 1/94-7/2000 | |
| PACY | Prairie Central Ry. Co. | added 10/81; eliminated 1/86 |
| PAE | Penn Central Transportation Co., Robert W. Blanchette, Richard C. Bond and John H. McArthur, Trustees | eliminated 4/76 |
| Peoria & Eastern Ry. | Jan-75 | |
| Consolidated Rail Corp. | added 4/76; 1/80-1/94; eliminated 7/99 | |
| Norfolk Southern Ry. Co. (Norfolk Southern) | Jul-00 | |
| PAGX | Planta Almacenadora de Gas, S.A. | 10/57-10/66; eliminated 4/69 |
| PAIX | Poly-America, Inc. | added 1/91; 1/94; eliminated 4/94; 7/2000 |
| PAL | Paducah & Louisville Ry., Inc. | added 10/86; 1/94-7/2000 |
| PALX | Prince Albert Refineries Ltd. | 10/57-4/61 |
| Pan American Liquids Service Co., Inc. | eliminated 4/78 | |
| PA&M | Pittsburgh, Allegheny & McKees Rocks R.R. | 4/38-10/66 |
| PAM | (PA&M) Pittsburgh, Allegheny & McKees Rocks R.R. Co. | 4/70; eliminated 4/89 |
| Pittsburgh, Allegheny & McKees Rocks R.R. Co. | 1/75-1/94; eliminated 1/95; 7/2000 | |
| PANX | Panoma Corp. | Jan-52 |
| Dorchester Corp. | 10/57-4/61; eliminated 4/62 | |
| Dorchester Gas Producing Co. | added 4/62; 7/65-4/70; eliminated 4/71 | |
| PAPX | Pennsylvania Pullmans Inc. | Jul-00 |
| PARX | Producers & Refiners Corp. (Sinclair Refining Co.) | Apr-38 |
| Sinclair Refining Co. | 1/52; eliminated 1/58 | |
| Union Tank Car Co. | 10/57; added 1/58; 4/61-10/66; eliminated 10/68 | |
| Pan American Ry. Co. | added 4/75; 1/80-7/2000 | |
| PARY | Prairie Trunk Ry. | 1/80; added 4/80; eliminated 10/87 |
| PASX | Pan-Am Southern Corp. | 1/52; eliminated 4/57 |
| American Oil Co. | added 4/57; 10/57-10/66; eliminated 4/68 | |
| Pacer International d/b/a Pace Stacktrain | added 4/2000; 7/2000 | |
| PATX | Pacific Tank Line | Apr-38 |
| PAUT | Pennsylvania and Atlantic R.R. Co. | Jan-75 |
| Consolidated Rail Corp. | Jan-80 | |
| PBBX | Ketchikan Pulp Co. | added 10/68; 4/70-1/75 |
| PBC | Pittsburg County Ry. | 4/38-1/52 |
| PBCX | Parker Brothers & Co., Inc. | added 1/74; 1/75; eliminated 4/76 |
| PBFX | IBP, Inc. | added 7/94; 7/2000 |
| PBGX | The Protane Corp. | 4/38-1/52; eliminated 1/53 |
| North American Car Corp. | added 7/64; 7/65-1/80; eliminated 7/82 | |
| PBL | The Philadelphia Belt Line R.R. Co. | 1/75-7/2000 |
| PBLX | The Pillsbury Co. | added 7/79; 1/80; eliminated 4/90 |
| PBLX | MHC, Inc., Wholly Owned Subsidiary of Con Agra, Inc. | added 4/90; 1/94; eliminated 1/2000; 7/2000 |
| PBNE | Philadelphia, Bethlehem and New England R.R. Co. | 4/38-1/94; eliminated 10/99; 7/2000 |
| PBR | Patapsco & Back Rivers R.R. Co. | 1/52-1/94; eliminated 10/99; 7/2000 |
| PBRR | Pine Belt Southern R.R. Co., Inc. | Jul-00 |
| PBVR | The Port Bienville R.R. | 1/75-1/80; eliminated 10/81 |
| Port Bienville R.R. | added 10/81; 1/94; eliminated 4/98; 7/2000 | |
| PBX | Barrett Division, Allied Chemical & Dye Corp. | 10/57; eliminated 7/58 |
| Barrett Division, Allied Chemical Corp. | added 7/58; eliminated 1/59 | |
| PC | Pacific Coast R.R. Co. | 4/38-10/66 |
| Penn Central Transportation Co. | Jan-75 | |
| Penn Central Transportation Co., Robert W. Blanchette, Richard C. Bond and John H. McArthur, Trustees | eliminated 4/76 | |
| Consolidated Rail Corp. | added 4/76; 1/80-1/94; eliminated 7/99 | |
| Norfolk Southern Ry. Co. (Norfolk Southern) | Jul-00 | |
| PCA | Penn Central Transportation Co. | Jan-75 |
| Penn Central Transportation Co., Robert W. Blanchette, Richard C. Bond and John H. McArthur, Trustees | eliminated 4/76 | |
| Consolidated Rail Corp. | added 4/76; 1/80-1/94; eliminated 7/99 | |
| PCAX | Pioneer Chlor Alkali Co., Inc. | added 1/91; 1/94; eliminated 7/94; added 10/96; 7/2000; eliminated 4/2001 |
| PCB | Penn Central Transportation Co. | Jan-75 |
| Penn Central Transportation Co., Robert W. Blanchette, Richard C. Bond and John H. McArthur, Trustees | eliminated 4/76 | |
| Consolidated Rail Corp. | added 4/76; 1/80-1/94; eliminated 7/99 | |
| PCC | Palouse River & Coulee City R.R. Inc. | Jul-00 |
| PCCX | Peabody Coal Co. (captive service) | added 10/57; 10/57-10/66 |
| Peabody Coal Co. | added 4/68; eliminated 10/68; 4/70; added 1/71; eliminated 4/72; 1/75-1/94 | |
| Peabody Coal Co. (captive service) | Jul-00 | |
| PCEX | Petromax Chemical Exchange, Inc. | added 7/80; eliminated 1/81 |
| PCFX | Pacific Car and Foundry Co. | added 7/82 |
| PCHX | Poole Chemical, Inc. | 1/94-7/2000 |
| PCIX | Shippers Car Line Corp. | Jan-52 |
| Shippers Car Line Division of ACF Industries, Inc. | 10/57-7/65 | |
| Pure Carbonic Co., a Division of Air Reduction Co., Inc. (Shippers' Car Line Division of ACF Industries, Inc.) | 10/66; eliminated 4/67 | |
| Airco Industrial Gases, a Division of Air Reduction Co., Inc. | added 4/67; eliminated 1/72 | |
| Airco Industrial Gases, a Division of Airco., Inc. | added 1/72 | |
| Shippers Car Line Division of ACF Industries, Inc. | Apr-70 | |
| Airco Industrial Gases, a Division of Airco, Inc. | eliminated 4/73 | |
| Shippers Car Line Division of ACF Industries, Inc. | 1/75-1/80; eliminated 4/88 | |
| ACF Industries, Inc. | added 4/88; 1/94-7/2000 | |
| PCLX | Polymer Corp. Ltd. | 1/52-10/66; eliminated 7/68 |
| PCMX | Petro-Chem Marketing, Inc. | added 1/65; 7/65-10/66; eliminated 7/68 |
| Petro-Chem Marketing Co. | added 7/68; 4/70-1/80; eliminated 4/92 | |
| PCN | Point Comfort & Northern Ry. Co. | 1/75-1/80; added 4/80; 1/94-7/2000 |
| PCRX | Pacer Rail Services, LLC | Jul-00 |
| PCSX | Pittsburgh Crucible Steel Co. | Apr-38 |
| Packers Cold Storage, Inc. | added 7/79; 1/80; eliminated 7/80 | |
| PLM International, Inc. | added 4/91; 1/94-7/2000 | |
| PCTX | Pioneer Cement Co. of Texas | 1/94-7/2000 |
| PCX | Pittsburgh Coal Carbonization Co. | Apr-38 |
| Packers Car Line Co. | added 4/57; 10/57-4/70 | |
| PCY | Pittsburgh, Chartiers & Youghiogheny Ry. Co. | 1/75-1/94; eliminated 7/97; 7/2000 |
| PDAX | Protex Industries, Inc. | 7/65-1/75; eliminated 4/78 |
| PDGX | The P.D. George Co. | 4/38-4/70; eliminated 7/70 |
| PDOX | Phelps Dodge Corp. | Apr-38 |
| PDQX | Callanan Equipment Corp. | added 10/67; eliminated 1/69 |
| Penn-Dixie Leasing Corp. | added 1/69; 4/70 | |
| Castle Capital Corp. | 1/75-1/94; eliminated 1/97; 7/2000 | |
| PDRR | Pee Dee River R.R. Co. | Jan-94 |
| Pee Dee River R.R. Corp. | added 1/95; 7/2000 | |
| PDSX | Pennsylvania-Dixie Cement Corp. | Apr-38 |
| Penn-Dixie Cement Corp. | 1/52-4/70 | |
| Penn-Dixie Industries, Inc. | 1/75-1/80 | |
| Penn-Dixie Cement Corp. | eliminated 10/81 | |
| PDTX | P.D. Transportation Co. | added 1/74; 1/75; eliminated 10/78 |
| PE | Pacific Electric Ry. | 1/52-7/65 |
| Peoria & Eastern Ry. | Jan-75 | |
| Consolidated Rail Corp. | 1/80-7/2000 | |
| P&E | Penn Central Transportation Co., Robert W. Blanchette, Richard C. Bond and John H. McArthur, Trustees | eliminated 4/76 |
| Consolidated Rail Corp. | added 4/76 | |
| PECX | Pioneer Equipment Co. | Jan-52 |
| Pekin Energy Co. | added 1/83; eliminated 7/84 | |
| General Electric Railcar Services Corp. | Jan-94 | |
| General Electric Rail Services Corp. | Jul-00 | |
| PEGX | Petroleum Gas Co. | added 10/60; 4/61-10/66; eliminated 1/69 |
| Falley Petroleum Co. | added 1/69; eliminated 4/69 | |
| Falley Corp. | added 4/69; eliminated 7/69 | |
| PEIX | Process Engineering Inc. | 1/80; eliminated 7/80 |
| PELX | Premier Equipment Leasing Co. | 1/94-7/2000 |
| PENX | Compania Minera de Penoles, S.A. | 10/57-4/61 |
| Metalurgica Mexicana Penoles, S.A. | 7/65-1/75; eliminated 7/76 | |
| Penford Products Co. | added 10/95; 7/2000 | |
| PEP | Portland Electric Power Co. | 4/38-1/52 |
| PEPX | Peppers Refining Co. | 4/38-1/52 |
| Potomac Electric Power Co. | added 1/75; 1/75-7/2000 | |
| PER | Port Everglade Ry. | 1/75-1/80 |
| PETX | The Petrol Corp. | Apr-38 |
| Petco Corp., Great Lakes Refining Division | Jan-52 | |
| Petco Corp. | eliminated 10/53 | |
| PF | The Pioneer & Fayette R.R. Co. | 1/75-7/2000 |
| PFE | Pacific Fruit Express Co. | 4/38-1/80; eliminated 4/89 |
| PFF | Pacific Fruit Express Co. | added 1/62; 7/65-1/75; eliminated 1/75 |
| PFMX | Perdue Transportation, Inc. | added 1/98; 7/2000 |
| PFRX | Parks Furniture Co., Inc. | added 4/85; eliminated 1/93 |
| Parks Propane & Appliance Inc. | added 1/93; 1/94; eliminated 4/2000; 7/2000 | |
| PFSX | Productos Forestales, S.A. | 1/52-7/65; eliminated 10/66 |
| Private Fuel Storage, LLC | added 7/2001 | |
| PFTX | Penick & Ford Tank Line (General American Transportation Corp.) | Apr-38 |
| The P. & F. Tank Line Co., Inc. | Apr-38 | |
| PGAX | Pressure Tank Car Co. | 7/65-1/75; eliminated 1/79 |
| Continental Tank Car Corp. | added 1/79; 1/80 | |
| PGBX | Peoples Gas By-Products Corp. | Apr-38 |
| PGCX | Poly Grinders Corp. | added 7/77; 1/80; eliminated 7/81 |
| Peoples Gas Systems, Inc. | 1/94-7/2000; eliminated 4/2001 | |
| PGDX | The Proctor & Gamble Manufacturing Co. | 1/94; eliminated 1/99 |
| General Electric Railcar Services Corp. | added 1/99; eliminated 1/2000 | |
| General Electric Rail Services Corp. | added 1/2000; 7/2000 | |
| PGE | Pacific Great Eastern Ry. Co. | 4/38-10/66 |
| British Columbia Ry. Co. | 1/75-1/80; eliminated 10/84 | |
| BC Rail Ltd. | added 10/84; 1/94-7/2000 | |
| PGER | British Columbia Ry. Co. | 1/75-1/80 |
| BC Rail Ltd. | eliminated 4/85 | |
| PGEX | Portland General Electric Co. | added 1/79; 1/80-7/2000 |
| PGHX | Trinity Rail Management, Inc. | added 10/98; 7/2000 |
| PGMX | The Procter & Gamble Manufacturing Co. | added 10/83; eliminated 4/88 |
| PGRV | Pigeon River R.R. Co. | added 1/86; eliminated 7/90; 1/94-7/2000 |
| PGRX | Petrolane Gas Service, Inc. | 7/65-1/80; eliminated 7/87 |
| Petrolane Gas Service Ltd. Partnership | added 7/87; 1/94; eliminated 10/95 | |
| AmeriGas Propane, L.P. | added 10/95; eliminated 4/98; 7/2000 | |
| PGSX | Propane Gas Service, Inc. | 1/52-4/61 |
| Apex Tank Car Line | 7/65-1/80 | |
| PGTX | Trinity Rail Management, Inc. | added 10/98; 7/2000 |
| PGX | The Procter & Gamble Transportation Co. (General American Transportation Corp.) | Apr-38 |
| PHCX | Harnischfeger Corp. | added 4/66; 7/65-10/66; eliminated 7/69 |
| PH&D | Port Huron and Detroit R.R. Co. | 7/65-10/66 |
| PHD | (PH&D) Port Huron and Detroit R.R. Co. | Apr-70 |
| Port Huron and Detroit R.R. Co. | 1/75-7/2000 | |
| PHDX | Phelps-Dodge Corp. | added 1/60; 4/61-1/75; eliminated 10/78 |
| PHL | Pacific Harbour Line, Inc. | added 4/98; 7/2000 |
| PHPX | Phosphate Products Division (Virginia-Carolina Chemical Corp., Phosphate Products Division) | Apr-38 |
| PI | Paducah & Illinois R.R. | 1/75-7/2000 |
| PICK | The Pickens R.R. Co. | added 7/73; 1/75-1/80; eliminated 10/92; eliminated 10/93; 1/94; eliminated 1/95; 7/2000 |
| PIFX | Pifer Tank Car Co. | added 10/87; 1/94-7/2000 |
| PIOX | Pioneer Iron & Metal Co. | added 4/71; 1/75; eliminated 7/79 |
| PIR | Pittsburgh Industrial R.R., Inc. (to POHC) | added 4/97; 7/2000; eliminated 4/2001 |
| PIVX | Pivotal Enterprises Corp. | Jul-00 |
| PIX | Publicker Industries, Inc. | Jan-52 |
| PJOX | P.J. O'Donnell & Sons | 1/52-7/65; eliminated 10/66 |
| PJR | Port Jersey | 1/75-7/2000 |
| PJRL | Penn Jersey Rail Lines Inc. | Jul-00 |
| PKHP | The Pickens R.R. Co. -- Honea Path Division | added 10/90; eliminated 1/91 |
| The Pickens R.R. Co. | added 1/91; eliminated 10/92; 1/94 | |
| Pickens R.R. Co./Honea Path Division | eliminated 1/95 | |
| The Pickens R.R. Co. -- Honea Path Division | Jul-00 | |
| PLCX | Plastics and Coal Chemicals Division, Allied Chemical Corp. | added 10/58; eliminated 4/61 |
| Plastics Division, Allied Chemical Corp. | added 4/61; 4/61; eliminated 7/64 | |
| Pullman Leasing Co., a Subsidiary of Pullman Inc. | 1/80; eliminated 4/81 | |
| Pullman Leasing Co. | added 4/81; eliminated 1/90 | |
| Itel Rail Corp. | added 1/90; eliminated 10/92 | |
| General Electric Railcar Services Corp. | added 10/92; 1/94; eliminated 1/2000 | |
| General Electric Rail Services Corp. | added 1/2000; 7/2000 | |
| PLE | The Pittsburgh & Lake Erie R.R. Co. | 1/75-1/80; eliminated 1/93 |
| Youngstown & Southern Ry. Co. | added 4/93; eliminated 10/93; 1/94-7/2000 | |
| PLEX | PLEX Division of PLM, Inc. | 1/80; eliminated 10/81 |
| PLM Remarketing Division of PLM, Inc. | added 10/81; eliminated 7/90 | |
| PLM International, Inc. | added 7/90; 1/94-7/2000 | |
| PLIX | Polysar Inc. | added 4/81; eliminated 4/92 |
| Polymont Plastics Corp. | added 4/92; 1/94-7/2000 | |
| PLM | Pullman R.R. Co. | Apr-38 |
| PLMX | Professional Lease Management, Inc. | added 4/74; 1/75; eliminated 1/78 |
| PLM, Inc. | added 1/78; 1/80; eliminated 7/84 | |
| PLM Financial Services, Inc. | added 7/84; eliminated 7/89 | |
| PLM International, Inc. | added 7/89; 1/94-7/2000 | |
| PLRX | PIC Trans, Inc. | Jul-00 |
| PLUX | The Plusar Equipment Corp. | Jul-00 |
| PLW | Pittsburgh, Lisbon & Western R.R. | 4/38-1/52 |
| PL&W R.R., Inc. | added 10/93; added 1/94; eliminated 1/96; 7/2000 | |
| PLWX | Pullman Leasing Co., a Subsidiary of Pullman Inc. | eliminated 1/90 |
| Pullman Leasing Co. | added 4/81; eliminated 1/90 | |
| Itel Rail Corp. | added 1/90; eliminated 10/92 | |
| General Electric Railcar Services Corp. | added 10/92; 1/94; eliminated 1/2000 | |
| General Electric Rail Services Corp. | added 1/2000; 7/2000 | |
| PLYX | United States Plywood Corp. | added 4/67; eliminated 7/69 |
| U.S. Plywood-Champion Papers, Inc. | added 7/69; 4/70; eliminated 10/72 | |
| Champion International Corp. | added 10/72; 1/75; eliminated 7/77 | |
| PM | Chesapeake and Ohio Ry. Co. | Oct-66 |
| Chesapeake and Ohio Ry. Co. (Pere Marquette Dist.) | 1/75-1/80 | |
| Chesapeake and Ohio Ry. Co. | eliminated 10/80 | |
| PMAX | PMA Transportation Corp. | added 1/79; 1/80; eliminated 1/94; 7/2000 |
| PMCX | Paper Makers Chemical Corp., Ltd. | Apr-38 |
| Peterson Manufacturing Co., Inc. | 1/52-10/57; eliminated 10/59 | |
| Plateau Mining Co. | added 7/79; 1/80; eliminated 4/87; 1/94 | |
| PMEX | Petroleos Mexicanos | 1/52-1/80; eliminated 10/90; 1/94 |
| PMGX | Pacific Metal, Ltd. | Jul-00 |
| PMIX | Pittman Moore, Inc. | added 1/94; 7/2000 |
| PMKY | Pittsburgh, McKeesport & Youghiogheny | 1/75-1/80 |
| PMLX | Prairie Malt Ltd. | added 4/97; 7/2000 |
| PMOX | Philip Morris, Inc. | Jul-00 |
| PMP | Paris & Mt. Pleasant R.R. | 4/38-1/52 |
| P&N | Seaboard Coast Line R.R. Co. | eliminated 4/75 |
| PN | Seaboard Coast Line R.R. Co. | 1/75-1/80 |
| PNER | Pocono Northeast Ry., Inc. | added 10/82; eliminated 4/89; eliminated 1/91; 1/94 |
| PNGX | The Peoples Natural Gas Co. | Apr-38 |
| PNHX | Public Service Co. of New Hampshire | Jan-94 |
| GATX Capital Corp. | added 7/95; 7/2000 | |
| PNR | Panhandle Northern R.R. Co. | Jul-00 |
| PNRX | Pioneer Oil & Refining Co. | Apr-38 |
| United States Atomic Energy Commission, Pittsburgh Naval Reactors Office | added 7/70; eliminated 4/74; 1/75-1/80 | |
| PNS | Philadelphia & Norfolk Steamship | 1/75-7/2000 |
| PNSX | Pacific Nuclear Systems, Inc. | added 1/88; 1/94; eliminated 4/95 |
| VECTRA Technologies, Inc. | added 4/95; eliminated 4/98 | |
| Chem-Nuclear Systems, LLC | Jul-00 | |
| PNTX | Putnam Tank Car Corp. | 1/75-1/80; eliminated 1/82 |
| QO Chemicals, Inc. | 1/94; eliminated 10/95 | |
| Great Lakes Chemical Corp., Specialty Chemicals | added 10/95; 7/2000 | |
| P&NW | Prescott & Northwestern R.R. | 4/38-10/66 |
| PNW | The Prescott and Northwestern R.R. Co. | 1/75-1/94; eliminated 1/2000; 7/2000 |
| PNWR | Portland & Western R.R., Inc. | Jul-00 |
| PNWX | Pacific Northwest Salvage, Inc. | added 4/81; eliminated 10/89 |
| POAK | Port of Oakland Ry. | 1/80-7/2000 |
| POHC | Pittsburgh & Ohio Central Rd. (was PIR) | added 4/2001 |
| POLX | Prest-O-Lite Co., Inc. | 1/52-4/61 |
| POPX | Pennsylvania Oil Products Refining Co. | Apr-38 |
| POR | Poseyville and Owensville R.R. Co., Inc. | added 1/88; eliminated 4/92; 1/94 |
| POTB | Port of Tillamook Bay R.R. | added 7/79; 1/80-7/2000 |
| POTX | Pargas Tank Cars, Inc. | added 10/65; 10/66; eliminated 1/68 |
| Pargas, Inc. | added 1/68; 4/70-1/80; eliminated 1/86 | |
| Suburban Propane Gas Corp. | added 1/86; eliminated 7/88 | |
| Suburban Propane--Division of Quantum Chemical Corp. | added 7/88; eliminated 4/90 | |
| General American Transportation Corp. | added 4/90; 1/94; eliminated 1/98 | |
| General American Marks Co. | added 1/98; 7/2000 | |
| P&OV | Pittsburgh & Ohio Valley Ry. | 4/38-10/66 |
| POV | (P&OV) Pittsburgh & Ohio Valley Ry. Co. | Apr-70 |
| POV | Pittsburgh & Ohio Valley Ry. Co. | 1/75-1/94; eliminated 1/96; 7/2000 |
| POVA | Pend Oreille Valley R.R., Inc. | added 1/80; 1/80; eliminated 1/85 |
| Pend Oreille Valley R.R. | added 1/85; eliminated 7/86; 1/94-7/2000 | |
| POWX | Power Silicates, Inc. | added 7/88; 1/94; eliminated 1/98; 7/2000 |
| POX | Alabama Power Co. | added 1/2000 |
| PPAX | Peoria Packing Co. | Apr-38 |
| PCS Phosphate Co., Inc. | added 4/99; 7/2000 | |
| PPBD | Port of Palm Beach District | 1/75-1/80 |
| PPCX | Peyton Packing Co. (Mather Stock Car Co.) | Apr-38 |
| Perfect Packed Products Co., Inc. | 1/52-10/57; eliminated 7/59 | |
| PPGX | Columbia-Southern Chemical Corp. | 1/52-10/57; eliminated 4/61 |
| Pittsburgh Plate Glass Co. | added 4/61; 4/61-10/66; eliminated 4/68 | |
| PPG Industries, Inc. | added 4/68; 4/70-7/2000 | |
| PPHX | National Car Co. | Jan-52 |
| PCS Phosphate Co., Inc. | added 10/97; 7/2000 | |
| PPIX | Pearl Packing Co. (National Car Co.) | Apr-38 |
| Fruit Growers Express Co. | 1/52-10/57 | |
| National Car Co. | eliminated 7/59 | |
| Pacific Petrochemicals, Inc. | added 10/65; 10/66; eliminated 7/68 | |
| Ashland Oil & Refining Co. | added 7/68 | |
| Pacific Petrochemicals, Inc. | eliminated 4/70 | |
| PPKX | (North American Car Corp.) | Apr-38 |
| PPLX | Pennsylvania Power & Light Co. | 7/65-7/2000 |
| PPNX | PCS Phosphate Co., Inc. | added 4/99; 7/2000 |
| PPPX | Pepin Pickling Co. | 4/38-1/52 |
| PPRX | Phillips Petroleum Co. | added 1/2001 |
| PPSX | Pacific Portland Cement Co. | Apr-38 |
| Pioneer Pipe & Supply Co., Inc. | Jul-00 | |
| PPTX | PCS Phosphate Co., Inc. | added 10/97; 7/2000 |
| P&PU | Peoria & Pekin Union Ry. | 4/38-4/70 |
| PPU | Peoria & Pekin Union Ry. Co. | 7/65-7/2000 |
| PPX | Pioneer Products Co. | Jan-52 |
| PQCX | Philadelphia Quartz Co. of California, Ltd. | 4/38-4/70; eliminated 1/71 |
| Philadelphia Quartz Co. | added 1/71; 1/75; eliminated 4/78 | |
| PQ Corp. | added 4/78; 1/80; eliminated 4/80; 7/2000 | |
| The PQ Corp. | added 4/80; 1/94; eliminated 1/95; 7/2000 | |
| PQX | Philadelphia Quartz Co. | 4/38-1/75; eliminated 4/78 |
| PQ Corp | added 4/78; 1/80; eliminated 4/80 | |
| The PQ Corp | added 4/80; 1/94-7/2000 | |
| PRAX | Pacific Rail Leasing Corp. | added 7/91; 1/94; eliminated 7/96 |
| First Union Rail | added 7/96; 7/2000 | |
| PRBX | Transcisco Leasing Co. | added 7/94; eliminated 7/97 |
| Trinity Rail Management, Inc. | added 7/97; 7/2000 | |
| PRCX | Praire Coal Ltd. | 1/94-7/2000 |
| PRDX | Pacific Rail Dismantling Services, Inc. | 1/94-7/2000 |
| PREX | REA Express | added 10/70; eliminated 4/74 |
| Pioneer Railroad Equipment Co. Ltd. | added 7/94; eliminated 4/97; 7/2000 | |
| PRFX | A.F. Pringle & Co., Inc. | Jan-52 |
| PRGX | Cargill, Inc. | added 4/98; 7/2000 |
| PRI | Port Railroad, Inc. | added 7/94; eliminated 7/96 |
| PRKX | The P. & P. Car Line, Inc. | 4/38-10/57; eliminated 10/58 |
| PRL | Penn Eastern Rail Lines, Inc. | added 4/98; 7/2000 |
| PRLX | Private Rail Ltd. | 1/94-7/2000 |
| PROX | Procor Ltd. | added 1/74; 1/75-7/2000 |
| PRPX | Transit Co., Ltd. | 4/38-1/52; eliminated 10/53 |
| Union Tank Car Co. | added 10/53; 10/57; eliminated 7/58 | |
| PRR | Pennsylvania R.R. | 4/38-10/66 |
| Penn Central Transportation Co. | 4/70-1/75 | |
| Penn Central Transportation Co., Robert W. Blanchette, Richard C. Bond and John H. McArthur, Trustees | eliminated 4/76 | |
| Consolidated Rail Corp. | added 4/76; 1/80-1/94; eliminated 7/99 | |
| Norfolk Southern R.R. Co. (Norfolk Southern) | added 7/99; 7/2000 | |
| PRRX | Pennsylvania Lines LLC | Jul-00 |
| PRSL | Pennsylvania-Reading Seashore Lines | Jan-75 |
| Consolidated Rail Corp. | 1/80-1/94 | |
| PRSX | Progress Rail Services Corp. | added 7/98; 7/2000 |
| PRT | Parr Terminal R.R. | 1/75-1/94; eliminated 7/97; 7/2000 |
| PRTD | Portland Traction Co., Portland R.R. and Terminal Division | 10/57-1/80; eliminated 10/89 |
| Portland Traction Co. | added 10/89; eliminated 7/92; 1/94-7/2000 | |
| PRV | Pearl River Valley R.R. Co. | 1/75-1/80; eliminated 10/86; 1/94-7/2000 |
| PRX | Palomar Oil & Refining Corp. | 1/52-4/61 |
| PRY | Pioneer Industrial Ry. Co. | Jul-00 |
| PRYL | Port Royal R.R. | 1/94-7/2000 |
| PS | The Pittsburgh & Shawmut R.R. Co. | 1/75-1/94; eliminated 7/96; 7/2000 |
| PSAP | The Puget Sound & Pacific R.R. Co. | Jul-00 |
| PSBX | Pacific States Railcar Co. | added 1/74; 1/75-1/94; eliminated 4/98 |
| PSCX | Prolerized Steel Corp. | added 7/60; 4/61-10/66; eliminated 10/69 |
| Public Service Co. of Colorado | added 4/73; 1/75-1/80 | |
| Public Services Co. of Colorado | 1/94-7/2000 | |
| PSEX | Public Service Electric & Gas Co. | Apr-38 |
| PSFL | Puget Sound Freight Lines | 1/75-7/2000 |
| PSHX | Puget Sound Railway Historical Association, Inc. | added 1/73; 1/75-1/80; eliminated 5/83 |
| PSIX | Public Service Co. of Northern Illinois | Jan-52 |
| Commonwealth Edison Co. | 10/57-7/65; eliminated 10/65 | |
| Public Service Co. of Indiana, Inc. | 4/70; added 10/70; 1/75-1/80; eliminated 1/91 | |
| PSI Energy, Inc. | added 1/91; 1/94-7/2000 | |
| PSL | Peabody Short Line R.R. | Apr-61 |
| Illinois Central R.R. | Jul-65 | |
| PSLL | Plymouth Short Line, Ltd. | eliminated 1/92; 1/94-7/2000 |
| PSLX | Portsmouth Division, Detroit Steel Corp. | 1/52-10/57; eliminated 1/59 |
| PSMX | Pennsylvania Salt Mfg. Co. | 4/38-1/52 |
| PSOX | Puget Sound Power & Light Co. | added 1/70; 4/70-7/2000 |
| PSPX | Phillips Petroleum Co. | 4/38-1/80; eliminated 7/86 |
| Phillips 66 Co., a Subsidiary of Phillips Petroleum Co. | added 7/86; 1/94; eliminated 10/95 | |
| Phillips Petroleum Co. | added 10/95; 7/2000 | |
| P&SR | Petaluma & Santa Rosa R.R. | 4/38-4/70 |
| PSR | Petaluma & Santa Rosa R.R. Co. | 7/65-10/66 & 1/75-1/80; eliminated 10/84 |
| Pittsburg & Shawmut R.R., Inc. | added 7/96; 7/2000 | |
| PST | Philadelphia Suburban Transportation | 1/75-1/80 |
| PSTB | Puget Sound Tug & Barge | 1/75-1/80 |
| PSTX | Puget Sound Pulp & Timber Co. | 1/52-4/61 |
| David J. Joseph Co. | added 4/99; eliminated 4/2000 | |