| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | over the [num ord] 30 years | 44 |
|
| 2 | over the [adj] 30 years | 44 |
|
| 3 | over the past 30 years | 42 |
|
| 4 | over the past 30 years | 42 |
|
| 5 | over the last 30 years | 33 |
|
| 6 | over the last 30 years | 33 |
|
| 7 | over the next 30 years | 11 |
|
| 8 | over the next 30 years | 11 |
|
