| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [noun] over the [num ord] twenty years | 30 |
|
| 2 | [noun sg] over the [adj] twenty years | 23 |
|
| 3 | [noun] over the last twenty years | 23 |
|
| 4 | [noun] over the last twenty years | 23 |
|
| 5 | [noun pl] over the [adj] twenty years | 12 |
|
| 6 | [noun] over the [adj] twenty years | 10 |
|
| 7 | [noun] over the past twenty years | 10 |
|
| 8 | [noun] over the past twenty years | 10 |
|
| 9 | [noun] over the next twenty years | 7 |
|
| 10 | [noun] over the next twenty years | 7 |
|
| 11 | [noun prp] over the [adj] twenty years | 5 |
|
