All of the algorithms in the Algorithm Marketplace have both monthly or annual subscription costs. Once you subscribe to an algorithm, you will have unlimited use of the algorithm for any of your surveys, and your account will be invoiced immediately. Note that you may unsubscribe from an algorithm at any time. For monthly subscriptions, once you unsubscribe, you will have access to the algorithm for the remainder of the current billing cycle. For annual subscriptions, you will continue to have access to the algorithm for the remainder of your subscription year, and effective the following year, you will no longer be billed or have access to the algorithm