Update README.md

README.md

@@ -34,7 +34,8 @@ The monthly processed data is located in `monthly_processed_data/` and contains
 | `station_name` | string | Name of the station |
 | `xml_station_name` | string | Station name from the XML response |
 | `eva` | string | EVA station number (unique identifier) |
-| `train_name` | string | Name of the train (e.g., "ICE 123", "RE 5") |
+| `train_number` | string | Train number / Zugnummer, the raw `tl.n` value identifying a specific train run (e.g., "123", "12603"). Combine with `train_type` for a label like "ICE 123" |
+| `line_number` | string | Line number / Liniennummer, the raw `ar.l`/`dp.l` value identifying the route, non-unique (e.g., "RB23", "14"); null for long-distance trains (ICE/IC/EC) where the API provides no line |
 | `final_destination_station` | string | Final destination of the train |
 | `delay_in_min` | integer | Delay in minutes |
 | `time` | timestamp | Actual arrival or departure time |