If you own more than one ship in one save slot, your company rating would be a combination of every Ship Rating in your fleet. Ratings can also fluctuate while you are sailing based on certain conditions. You can have as many as 5 stars per ship. There is 5 different categories that combined create your overall Ship Rating.
And since there is a bonus available for better ratings, it might be a good idea to understand how to improve on each ratings category.
