How to calculate headline metrics?

Question

Business Informatics

Friends, how can I determine (calculate) metrics for headlines?

Open rate - the percentage of subscribers who viewed / opened the letter.
Click-through rate (CTR) is the percentage of subscribers who clicked on one of the links in the email.
CTOR - navigation through the letter.
Applications/ Clicks - conversion from clicks to applications.

Answer 1

The case smells like an infinite decimal fraction or the ratio of the number of certain site actions to the response number of user actions (per site actions)