| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [noun pl] over the [num ord] 20 years | 14 |
|
| 2 | [noun pl] over the [adj] 20 years | 11 |
|
| 3 | [noun pl] over the past 20 years | 10 |
|
| 4 | [noun pl] over the past 20 years | 10 |
|
| 5 | [noun pl] over the last 20 years | 7 |
|
| 6 | [noun pl] over the last 20 years | 7 |
|
| 7 | [noun pl] over the next 20 years | 7 |
|
| 8 | [noun pl] over the next 20 years | 7 |
|
