| Similarity | Rank | |
|---|---|---|
| 1960 | 0.925 | 2807 |
| 1940 | 0.878 | 7398 |
| 1970 | 0.875 | 2583 |
| 1930 | 0.868 | 4100 |
| 1920 | 0.864 | 5459 |
| 1980 | 0.817 | 2404 |
| 1870 | 0.778 | 11182 |
| 1900 | 0.773 | 20137 |
| 1880 | 0.761 | 9812 |
| 1890 | 0.757 | 10843 |
| post-war | 0.752 | 4355 |
| mid-1960s | 0.749 | 19473 |
| 1800 | 0.734 | 33369 |
| nineteenth | 0.731 | 2686 |
| mid-1960 | 0.728 | 49947 |
| mid-1970 | 0.728 | 12406 |
| 1910 | 0.720 | 77774 |
| mid-1980 | 0.718 | 11219 |
| twentieth | 0.715 | 3963 |
| decade | 0.711 | 1661 |
| mid-nineteenth | 0.710 | 18774 |
| mid-to-late | 0.701 | 71501 |
| 1960s | 0.695 | 56848 |
| mid-1950s | 0.694 | 24366 |
| 1860 | 0.693 | 11907 |