For variable rate loans, Aven uses two different Indicies. Your Cardholder agreement will specify the Index used for your account.
Wall Street Journal Prime (WSJ Prime): The Wall Street Journal surveys some of the country's biggest banks and publishes a consensus rate based on the survey. This is one of the most common indicies used for many lending products. Look up the latest rates on the website of the Wall Street Journal. https://www.wsj.com/market-data/bonds/moneyrates
Federal Funds Target Rate - Upper Limit (FFTR-UL): This rate is set by the Open Market Committee of the US Federal Reserve (FOMC). It is the short-term interest rate at which U.S. Banks and Credit Unions lend to each other overnight within the Federal Reserve system. Look up the latest rates on the website of the St. Louis Fed. https://fred.stlouisfed.org/graph/?g=QGiM
The rate on your account is the sum of the index and the margin. Both can be found in your Account Agreement.