| Similarity | Rank | |
|---|---|---|
| 1920 | 0.882 | 5459 |
| 1950 | 0.868 | 3691 |
| 1960 | 0.847 | 2807 |
| 1940 | 0.842 | 7398 |
| 1970 | 0.806 | 2583 |
| 1870 | 0.796 | 11182 |
| 1880 | 0.793 | 9812 |
| post-war | 0.785 | 4355 |
| 1900 | 0.770 | 20137 |
| 1890 | 0.765 | 10843 |
| 1840 | 0.750 | 13067 |
| 1830 | 0.749 | 13819 |
| interwar | 0.749 | 19545 |
| inter-war | 0.747 | 11074 |
| 1860 | 0.746 | 11907 |
| 1800 | 0.743 | 33369 |
| heyday | 0.742 | 14276 |
| nineteenth | 0.741 | 2686 |
| 1980 | 0.739 | 2404 |
| mid-nineteenth | 0.735 | 18774 |
| mid-1960s | 0.733 | 19473 |
| mid-1960 | 0.729 | 49947 |
| pre-war | 0.727 | 9050 |
| mid-1970 | 0.726 | 12406 |
| 1820 | 0.722 | 20795 |