Saint-Cyr-les-Champagnes (first part, French meaning Saint Cyrus) is a commune in the canton of Lanouaille of the Dordogne department in Aquitaine in southwestern France.
| Year | Population | Density | Percent of the canton |
|---|---|---|---|
| 1962 | 395 | - | - |
| 1968 | 457 | - | - |
| 1975 | 380 | - | - |
| 1982 | 339 | - | - |
| 1990 | 313 | - | - |
| 1999 | 295 | 18/km² | - |