| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [noun] over the [num ord] twenty years | 30 |
|
| 2 | [noun] over the last twenty years | 23 |
|
| 3 | [noun sg] over the [num ord] twenty years | 15 |
|
| 4 | [noun pl] over the [num ord] twenty years | 11 |
|
| 5 | [noun] over the next twenty years | 7 |
|
