How is your working time distributed between coding and thinking?
It depends. At this time of the year, I'm mostly doing bug fixes, so thinking is the majority of my work effort.
As a side note, I think in typical software companies thinking is not part of the culture anyway: you are usually supposed to be sitting there at your computer typing something. You will almost definitely be noticed by your managers if you wander about with a blank look thinking over your next steps with your code.
You will find that this attitude is not limited to software companies. It is a widespread phenomenon in American corporate culture. My experience is that managers who spent significant time in the military (or when younger in military styled schooling) pick up a habit of always be working. If your Seargant catches you not working (and since thinking is not visible to an external viewer, thinking == goofing off), he'll order you to scrub the sidewalks with a toothbrush (or other stupid make-work) just to keep you from goofing off. The all-time worst manager I worked for would intentionally create a crisis in order to make work for you if he catches you doing nothing - and since he was also the owner, he didn't believe that you needed to think about anything, just get it done.