The website only looks at the get_account database api, and stores the values. I haven't stored any content or vote to know who gets how much rewards, just looking hourly the get_account api, and storing in a db. Since the data importer for the website has only been running for a week now, that's why you only see 7 days.
If we wanted to see earlier than 7 days, we would need to setup a node with the api enabled, and slowly play out the blockchain day by day, while storing daily records in a database.
Sorry if i'm not anwering your question correctly but i'm having abit of trouble understanding it.