About Custom Reports
A custom report is a report that you create. You pick the dimensions (City and Browser, for example) and metrics (Visits, Pageviews, and Bounce Rate, for example) and decide how they should be displayed. To access your custom reports, click the Customization tab. Your reports will be listed in the left navigation under Custom Reports. (If no custom reports have been created, you will only see an entry for Overview under Custom Reports.)
To create a custom report, click the Customization tab and then click Overview under Custom Reports in the left navigation. Click + New Custom Report to create a new report. Read Creating Custom Reports to learn more.
To edit or delete an existing custom report, click the Customization tab and then click Overview under Custom Reports in the left navigation. You can edit or delete existing reports from the Overview. Read Managing Custom Reports to learn more.
About Dimensions and Metrics in Custom Reports
To build a custom report, you'll need to specify at least one dimension and one metric. Dimensions are ways of describing visits, visitors, pages, products, and events. Examples of dimensions include Visitor Type (whether new visitor or returning visitor), Source (the name of a referring website/search engine ), Page Title (the HTML title of a page on your site), and Product SKU (the SKU code for a product purchased on your site).
Metrics are the numeric measurements. For example, "there were N Pageviews and N Transactions from new visitors and N Pageviews and N Transactions from returning visitors." Pageviews and Transactions are the metrics and Visitor Type is the dimension.
Some metrics and dimensions can't be paired in a custom report. For details, refer to Valid Dimension-Metric Combinations.