# Aggregates table

Use this table to specify the group you want to aggregate, the aggregation method, and the name of the resulting new field. Click **Get lookup fields** to specify the fields to include in a group. See the [Group By](https://docs.pentaho.com/pdia-data-integration/9.3-data-integration/pdi-transformation-steps-reference-overview/group-by-landing-page-article) step for more details.

| Column      | Description                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
| ----------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| **Name**    | The name of the aggregate field.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |
| **Subject** | The subject on which you want to use an aggregation method.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
| **Type**    | <p>The type of aggregation method for grouping the rows. The following methods are available:</p><ul><li>Sum</li><li>Average (Mean)</li><li>Median</li><li>Percentile</li><li>Minimum</li><li>Maximum</li><li>Number of values (N)</li><li>Concatenate strings separated by , (comma)</li><li>First non-null value</li><li>Last non-null value</li><li>First value (including null)</li><li>Last value (including null)</li><li>Standard deviation</li><li>Concatenate strings that are separated by the character specified in the <strong>Value</strong> column</li><li>Number of distinct values</li><li>Number of rows (without field argument).</li></ul> |
| **Value**   | The aggregate value.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |