does anyone know what are the drop rates of dungeon exotics, and does completing the whole dungeon or the 3rd encounter increase the drop rate according to what people say?.

like I hate how there is zero in-game info of what the drop rates are of exotics, and I wished I got info on what can be done to increase the drop rates, do you need to complete the entire dungeon to increase the drop rate, or you can just complete the 3rd encounter?

and does anyone know what are the exact drop rate increase percentages of triumphs?, because in-game there is no info of how much it is, and if its like a 1-2% increase then I'm not doing those, especially with sundered doctrine being the hardest dungeons released.