Yet Another Mail Merge tracks the number of recipients who clicked on any links from your email. You will be able to get the click-through rate directly on the tracking report.
What is the click-through rate?
'Click-through rate (CTR) is the ratio of users who click on a specific link to the number of total users who view a page, email, or advertisement. It is commonly used to measure the success of an online advertising campaign for a particular website as well as the effectiveness of email campaigns.' (Wikipedia)
How do we track CTR?
For the moment, we only track if your recipient has clicked at least once in any of the links in your emails. The click-through rate will help you measure the success of your emailing campaigns, and should give you more useful information than the open rate only.
In the future, you might be able to get even more precisions (which link(s) were clicked, how many times etc.) in your dashboard through the web app.
Besides, you might notice that your links have been changed in your emails, starting with 'https://yourdomain-dot-yamm-track.appspot.com/Redirect?ukey='. That is normal; this redirection is necessary for the click tracker to work correctly.