Exactly 20 years ago a great uncle opened a new investment account that paid some fixed APR, compounded quarterly. Your uncle deposited $1,000 when the account was opened, and continued to make annual $1,000 deposits (the last deposit was made this morning). Your uncle has informed you that he is transferring the account to you as a gift, and that the account now has a balance of $35,270.94. What is the APR the account has been paying?