Once your Performance Max campaign has been serving you may want to compare the
performance with your existing campaigns to understand where it is bringing
value and where you might want to make improvements.

Before you compare performance of campaigns, it is recommended you run campaigns
for at least 6 weeks to allow Google AI time to ramp up and curate sufficient
data to compare performance.

## Compare reports

Our guide on [Performance Max reporting](https://developers.google.com/google-ads/api/performance-max/reporting) is the first place to start to
understand which attributes and metrics are compatible with Performance Max and
how to retrieve them using [`GoogleAdsService.SearchStream`](https://developers.google.com/google-ads/api/reference/rpc/v26/GoogleAdsService#searchstream).

This section will cover which resources are comparable between Performance Max
and other campaign types.

> [!NOTE]
> **Note:** Since Performance Max lets you unlock new audiences across Google's channels and networks, you might find that there may not be a direct comparison available between metrics you use in existing campaigns and those in Performance Max. Make sure to compare the performance of all existing campaigns with exposure to the audiences Performance Max can reach. This will ensure you see the whole picture. This guide will explain new reporting views to access performance data and the best mapping you can make between similar sources.

### Asset groups instead of ad groups

Performance Max campaigns use the concept of [asset groups](https://support.google.com/google-ads/answer/10724748) which are a set
of creatives that will be used to create an ad depending on the channel it's
being served on. Similar to ad groups in other campaigns, you should use them to
group assets, such as text, images and video, by a common theme. Google AI will
assemble the assets in an asset group into all applicable ad formats for your
goal and show the most relevant creative for your campaign.

Although the specific resources (asset group assets and ad group ads) in both
types of group are different it is a good place to start investigating
comparable performance especially if you used the data from an existing ad group
to create an equivalent asset group.

Here are a few examples of resources and reporting views that are similar in
Performance Max:

| Your current resource or view | Performance Max similar resource or view | Notes |
|---|---|---|
| `https://developers.google.com/google-ads/api/fields/v26/ad_group` | `https://developers.google.com/google-ads/api/fields/v26/asset_group` | As both group by theme, metrics such as `https://developers.google.com/google-ads/api/fields/v26/asset_group#metrics.conversions` can be compared for the theme. |
| `https://developers.google.com/google-ads/api/fields/v26/ad_group` | `https://developers.google.com/google-ads/api/fields/v26/asset_group` | As a collection of assets are used to generate ads, some structural data can be found at this level, such as `https://developers.google.com/google-ads/api/fields/v26/asset_group#asset_group.final_urls`. |
| `https://developers.google.com/google-ads/api/fields/v26/ad_group_criterion` | `https://developers.google.com/google-ads/api/fields/v26/asset_group_listing_group_filter` | Only for campaigns with product or listing groups. |
| `https://developers.google.com/google-ads/api/fields/v26/product_group_view` | `https://developers.google.com/google-ads/api/fields/v26/asset_group_product_group_view` | Only for campaigns with product feeds. |

### Search Terms Performance

If you are looking for metrics on search term performance, use
[`campaign_search_term_view`](https://developers.google.com/google-ads/api/fields/v26/campaign_search_term_view) to find data for both Performance Max and
search network campaigns aggregated at the campaign level.

For more details and information about search term insights, see [Search terms
performance](https://developers.google.com/google-ads/api/performance-max/campaign-criterion-reporting#search-terms-performance).

## Optimization \& Troubleshooting

For more best practices for optimizing and troubleshooting Performance Max
campaigns, see our [Performance Max optimization and troubleshooting guide](https://developers.google.com/google-ads/api/performance-max/troubleshooting).