I have a dataframe like this a column like this

```
COL1      
RED[10%(INC)]
RED[12%(INC)]

```

and I want create `col2` as this

```
COL2
10
12

```

Could cou help me to find the good regex?
I tried this:

```
RED\[(\d+\.\d+) %INC\]

```

but it doesn't walk.