User blog comment:Kitahara/Recording drum expedition success rates/@comment-25977430-20150129232738/@comment-25832576-20150130051912

Sshinka, I think you have misunderstood this test's purpose. Up until Faeriedust's post, drum expeditions were considered/assumed to have a base 50% rate + 16% which was clearly not case, and thus the 8% was placed as a stopgap solution despite not having any proof to back it up. As Zel-Melon stated, this test's purpose is to find the real numbers behind the success rates (or at least come closer to it than just pulling numbers out of our ass).

We've since noticed trends that indicate base rates may not even be 50%, which would smash the above formula that you and many others (inlcuding myself) had previously thought to be correct. Hell just check out expedition 21's success rate with 3 sparkled ships, it certainly doesn't fit in with the current formula.