| 1 | DTDX | Dow Chemical Co., Texas Division | 4/1961; added 10/1961; 7/1965; eliminated 1/1966 | | NAKINA |
| 2 | DTDX | General American Transportation Corp. | added 7/1958; eliminated 10/1958 | | NAKINA |
| 3 | DTDX | Dow Chemical Co., Texas Division | 1/1943-10/1957; eliminated 7/1958 | | NAKINA |
| 4 | DTDX | Dow Chemical Co., Texas Division | 1/52-10/57; eliminated 7/58 | | NRHS |
| 5 | DTDX | General American Transportation Corp. | added 7/58; eliminated 10/58 | | NRHS |
| 6 | DTDX | Dow Chemical Co., Texas Division | 4/61-7/65; eliminated 1/66 | | NRHS |
| 7 | DTDX | DOW CHEMICAL CO., TEXAS DIV. (GENERAL AMERICAN TRANSPORTATION CORP.) | | | PWRC |
