This work is so far out of left field for anon, I'd be surprised if it was more than one person. The report is concise and coherent, a step above previous missives left by the group. I'm almost certain it's the work of a single young analyst at an established firm. Otherwise they've made a very structured entrance into financial analysis, impressive given their usually decentralized and distanced nature.
I'll say that even my engineering team technical reports in university, among students who met face to face during the week, usually did not sound as cohesive as this report.
On the last page of the report it mentions many people working on it, but unaware of the final product, but with the team being rewarded. It also mentions a codeword to decrypt source information that they'll release should the team be threatened. As the team met with the company, the company may well have identified them by now, or narrowed it down.
Add:
The team obviously (re)branded themselves Anonymous to take any heat off their own identities or firm, whilst also giving the report a publicity boost within the context of the newly setup http://anonanalytics.com/ - they also have some technical know-how to encrypt the data: that may have come from more conventional Anon members. Also, being part of Anonymous may scare the target firm's executives into not retaliating - that's smart.
I'll say that even my engineering team technical reports in university, among students who met face to face during the week, usually did not sound as cohesive as this report.