Total babies named Irja (all years): 156
| Year | Girls (count / rank / %) |
|---|---|
| 1930 | 5 / #4859 / 0.000% |
| 1926 | 5 / #5205 / 0.000% |
| 1924 | 5 / #5430 / 0.000% |
| 1921 | 12 / #2849 / 0.001% |
| 1920 | 10 / #3213 / 0.001% |
| 1919 | 18 / #2025 / 0.002% |
| 1918 | 20 / #1916 / 0.002% |
| 1917 | 14 / #2374 / 0.001% |
| 1916 | 14 / #2312 / 0.001% |
| 1915 | 17 / #1916 / 0.002% |
| Year | Girls (count / rank / %) |
|---|---|
| 1914 | 10 / #2339 / 0.001% |
| 1913 | 10 / #2092 / 0.002% |
| 1912 | 5 / #3181 / 0.001% |
| 1911 | 5 / #2653 / 0.001% |
| 1910 | 6 / #2269 / 0.002% |