I know the definition of "coding time" can vary but let's be reasonable and human here, of course coding time is more than the time spent typing actual characters in your editor. Taking a few minutes to read some doc, search the web for a function or to type a few VCS commands count as "coding". On the other hand, spending 30 minutes reading a manual does not. You get the idea.
That being said, let's take a developer working 7 to 8 hours a day (regular day job for example). What would be your estimation of his daily actual coding time? On average, of course.
P.S.: This is not a question related to productivity measuring or anything, just plain curiosity.