how can this if and statement be written in derived column.

```
IF(AND(AD2>-1,AD2<16),"0-15 Days",(IF(AND(AD2>15,AD2<31),"15-30 Days",(IF(AND(AD2>30,AD2<91),"30-90 Days",(IF(AD2>90,"90+Days",AD2)))))))

```

how can this be written in derived column