Re: Is "it" the same thing as covered in the last sentence?
Depends. The previous sentence is "Numbers?", and "it" does refer to numbers and should probably be "them". The intended meaning is "71% don't require a number". This is consistent with 63% not having a minimum length and 72% not requiring a mix of upper and lowercase characters. However, your reading comprehension is such that I doubt you registered the "Numbers?" sentence at all, or didn't realise it wasn't a reference to the percentages, and you also missed that the sentence before that mentions password length as well as special characters. A password complexity algorithm would estimate the entropy of a given password, which is different to merely checking whether it contains a number.
So it's actually pretty coherent, apparent from the it/them grammar mistake.
Biting the hand that feeds IT
