We provide 30 days of historical data in the Competitor tracking section, it's not possible to view data going back further than this.
That being said, you can schedule recurring Competitor exports from the Reports section, allowing you to keep a record of your competitor data for more than 30 days. Learn how to set up Competitor reports here!
You can also export the Competitor Overview table in both CSV and PNG format for a detailed summary of the performance of your competitors over the past 30 days. Just head to the Competitors overview, and click the export icon at the top right of the Competitive table, then choose between a CSV or PNG export format: