Click-Through Rate
Your click-through rate is clicks divided by impressions and is often abbreviated as CTR. So if you have five clicks for every hundred times your advertisement is shown, your CTR is 5%. Per the 2018 rules, Grantees are required to have at least a 5% CTR for their entire account. A 5% success rate may sound like an easy goal to achieve, but it is something that a lot of nonprofits struggle with and is the rule of greatest concern amongst many new standards that were part of that announcement. Keep in mind that not only do people see other ads and ordinary website listings when they make a search, but also that some people prefer to click on an ordinary website listing over an advertisement.
Read Google’s definition.