Have you considered the amount of productive time you either add or subtract from the whole with your posts. Like this one maybe you prevented someone from working for 5 minutes and he had not gain.
But maybe you inspired someone to make better use of there time and do something awesome. The quandary's of life.
Since blogging means 100% fun to me, it definitely ADDS value (time) to my life's account :-) And if I could inspire others, well even better!
Thanks for stopping by!