I don't think you will find reliable data on what you're looking for. I've been looking for that kind of figures for a few years and I haven't found them.
First of all, very few organisations tell you what method they are using. Some just don't use any. Some other don't know what they use, or what to call it. And some know what to call it, but won't disclose it for whatever reasons. Of the organisations that will tell you, which are (in my experience) a minority, there's a big assymetry in how they characterise what they tell you. The way in which your own question is worded illustrates this: most industry people (and many academics) today, when asked to list methodologies, think of waterfall, RUP, Scrum, XP, and a few other "trademarked" agile approaches. It is interesting, but they are perfectly capable of citing a number of agile approaches, the differences between which are usually much smaller than the differences between (almost forgotten) methods that are bunched together under "waterfall". Agile approaches are so heavily marketed and hyped that, like Coca-Cola or McDonald's, are so present in our daily lives.
Methodologies are often presented as either waterfall or agile. That is a terrible fallacy, fostered by the agile community. There are successful methodologies that do not qualify as waterfall and predate (and do not qualify as) agile. However, they seem to be ignored, and they rarely surface on surveys such as the one you demand in your question. Very rarely I find people in industry reporting to use methods such as Catalysis, OPEN/Metis or Fusion.
(Note: Don't misunderstand me; I appreciate the value and contributions of the agile movement. But I am no raving fan; I am a researcher who tries to make an objective assessment.)
In summary, I don't think you'll find a study with data that answers your question. But, in your search, I suggest you take into account these comments.
Good luck. :-)