Sure! To go back to being a registered user, you'll need to click the red Unsubscribe button on the My Subscription page (via the Account tab at the top right). At that point, you'll still be able to view the site but will have a registered user's limited access to its content. You can also choose to wait until closer to the end of your subscription plan before unsubscribing.
Please keep in mind that if your account remains inactive for a period of two years, it will have to be closed permanently. Any saved material will be emailed to you and your personal information will be deleted from our system. Should you wish to re-subscribe at that point, you would need to start over with a new account.