(insurance demutualization basis case; court determines that plaintiff failed to establish that any of the premiums paid were for membership rights in insurance company; consequently, plaintiff did not have an income tax cost basis in share of stock issued on demutualization when shares eventually sold in 2005; plaintiff failed to offer evidence of purchase price paid for membership rights in particular as opposed to policy as a whole; thus, plaintiff failed to satisfy proof burden that income tax basis other than zero; facts of case distinguishable from those in Fisher, et al. v. United States, 82 Fed. Cl. 780 (2008)).