My thought is it is impossible to feel depressed if you walk 30,000 steps a day.
This is what I have noticed, my overall mood is highest when I walk the most. When I walk less, I feel less zest and passion in life.
Therefore, as a new year goal make it a goal to walk 30,000 steps a day. Granted, you might not reach it (I have not yet), but the thought is it is better to set an insanely high and audacious goal and slightly miss it, then set a small goal and meet it.