| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | there have been a steady increase | 6 |
|
| 2 | there [verb] been a steady increase | 6 |
|
| 3 | there [vb -s] been a steady increase | 5 |
|
| 4 | there has been a steady increase | 5 |
|
