Response rates are measured upon your response to enquiries and exchange proposals. If you haven't responded to one, your response rate will be below 100% It's important to answer all messages and proposals as people are more likely to send you enquiries if they know you'll answer. Anyone can see how many enquiries and proposal you have had, and how many you've responded to. If you can't immediately see which enquiry or proposal requires a response, there's a filter on the exchanges and messages page (the envelope icon).