# percentDifference


The `percentDifference` function calculates the percentage difference between the current value and a comparison value, based on partitions, sorts, and lookup index. 

## Syntax


The brackets are required. To see which arguments are optional, see the following descriptions.

```
percentDifference
(
  measure 
  ,[ sortorder_field ASC_or_DESC, ... ]  
  ,lookup index
  ,[ partition_field, ... ] 
)
```

## Arguments


 *measure*   
An aggregated measure that you want to see the percent difference for. 

 *sort order field*   
One or more measures and dimensions that you want to sort the data by, separated by commas. You can specify either ascending (**ASC**) or descending (**DESC**) sort order.   
Each field in the list is enclosed in \$1\$1 (curly braces), if it is more than one word. The entire list is enclosed in [ ] (square brackets).

 *lookup index*   
The lookup index can be positive or negative, indicating a following row in the sort (positive) or a previous row in the sort (negative). The lookup index can be 1–2,147,483,647. For the engines MySQL, MariaDB and Aurora MySQL-Compatible Edition, the lookup index is limited to just 1.

 *partition field*   
(Optional) One or more dimensions that you want to partition by, separated by commas.   
Each field in the list is enclosed in \$1\$1 (curly braces), if it is more than one word. The entire list is enclosed in [ ] (square brackets).

## Example


The following example calculates the percentage of difference between the `sum(Sales)` for the current and the previous `State`, sorted by `Sales`.

```
percentDifference
(
  sum(amount), 
  [sum(amount) ASC],
  -1, 
  [State]
)
```

The following example calculates the percent that a specific `Billed Amount` is of another `Billed Amount`, sorted by (`[{Customer Region} ASC]`). The fields in the table calculation are in the field wells of the visual.

```
percentDifference
(
  sum( {Billed Amount} ), 
  [{Customer Region} ASC],
  1
)
```

The following screenshot shows the results of the example. The red letters show that the total `Billed Amount` for the `Customer Region` **APAC** is 24 percent less than the amount for the **EMEA** region.

![\[alt text not found\]](http://docs.amazonaws.cn/en_us/quick/latest/userguide/images/percentDifference.png)