BN
| Burlington Northern | 1 |
BNSF
| BNSF Railway | 2 |
BO
| Baltimore & Ohio | 3 |
CN
| Canadian National Railways | 1 |
CS
| Colorado & Southern | 1 |
CSX
| CSX Railroad | 3 |
DME
| Dakota, Minnesota and Eastern | 1 |
DTI
| Detroit Toledo & Ironton | 1 |
GN
| Great Northern | 1 |
ITC
| Illinois Terminal Railroad | 1 |
MKT
| Missouri-Kansas-Texas | 1 |
MP
| Missouri Pacific | 2 |
SBD
| Seaboard System | 2 |
SP
| Southern Pacific | 1 |