The ratings system explained after the jump!
According to Hall, there are two things to remember for this game: the closeness of the firework to the target line, and the number of perfect button presses you get.
First off, the game assigns the visual rating for your firework depending on how close it is to the target line. Only when it's really close do you get the "Perfect" Rating. Second, and more importantly, it takes a lot of perfect ratings to achieve the best honors. You get an A* if you get at least 25% of your detonations perfect, A** at 50%, and A*** at 75%.
That's the ratings system in a nutshell. If you wanna find out more about the system, feel free to check out the source link for additional info.
