I think it's at the below link and yes it's strangely missing. Do you want to open a lab ticket?
I recommend the summary fields extension:
It'll keep a calculated copy of the last contribution amount (and many other useful fields) as custom fields of the contact, making reporting like this much easier.
Because contributions are stored in a separate table, generating fields like 'last contribution' tends to ...
If you run it manually from the scheduled jobs screen you need to edit the mail report entry there and set those parameters. Normally you would set them in the specific command you use for cron for a specific report.
See https://docs.civicrm.org/user/en/latest/initial-set-up/scheduled-jobs/#job_mail_report. For getting the instance id that's a good point. ...
I was able to do this with a Drupal View and adding the Views Aggregator Plus module.
I created a view using Contributions. The format was Table with Aggregation Options.
I added the Filter Criteria and Fields that I wanted to display.
In the Format:Settings--
I "grouped and compressed" the Recurring Id field
"Count" the Contribution ID ...