Honestly 16 Days?
Just started playing this game 2nd season now. But I can't follow the logic that some say a Stadium is a source of income. The upgrades take a long time and the costs are high. Even when putting the ticket sales to $5 (Fills my stadium to max) it will take roughly 3 seasons to get my investment back. (Includes playing CL and Cup)
Next to that, nobody confirmed that the amount of supporters watching a match does influence the score.
Although I think a fully upgraded stadium can be an eye catcher. And that the upgrades are obliged to upgrade other facilities for which I think are more useful. Like Pitch, Medical, Training and Youth.
If anyone can confirm that they make more money out of the Stadium in one season, please explain how.