# expand\_to\_gvkeyiid

### Description

FinHelper expand\_to\_gvkeyiid function expands data with IDs in `gvkey` format to the `gvkeyiid` format.

### **Parameters**

* `df` (pandas.DataFrame): CM with gvkey (ex. factor, financial)

### **Returns**

* `pandas.DataFrame`

### **Example**&#x20;

```python
# df is financial, factor gvkey cm
gvkeyiid_df = FinHelper.expand_to_gvkeyiid(df)
```
