Yes, it is possible to link invoices and credit memos in one report in NetSuite. You can do this by creating a custom report that includes both invoice and credit memo data. The report can then be used to track the total amount of revenue generated by invoices and the total amount of refunds issued by credit memos.

Here are the steps on how to create a custom report that includes both invoice and credit memo data:

1. Go to Reports > Custom.
2. Click New.
3. In the Type field, select Transaction.
4. In the Name field, enter a name for the custom report.
5. In the Criteria section, add the following filters:
   • Type: Invoice
   • Status: Posted or
   • Type: Credit Memo
   • Status: Posted
6. In the Available Fields section, add the following fields:
   • Invoice Number
   • Credit Memo Number
   • Customer
   • Amount
   • Date
7. In the Columns section, add the following columns:
   • Invoice Number
   • Credit Memo Number
   • Customer
   • Amount
   • Date
8. Click Save.

This will create a custom report that includes both invoice and credit memo data. The report can then be used to track the total amount of revenue generated by invoices and the total amount of refunds issued by credit memos.

Here is an example of how to use the custom report to track the total amount of revenue generated by invoices and the total amount of refunds issued by credit memos:

1. Go to Reports > Custom.
2. Click View next to the custom report you created.
3. In the Filter section, select the date range you want to track.
4. Click Run.

The report will display the total amount of revenue generated by invoices and the total amount of refunds issued by credit memos for the selected date range.