Flay should disagree with both Cora and Batali. According to Standard 5.A.2. For periods beginning on or after January 1, 2011, firms must present for each annual period:

1. Three-year annualized ex-post standard deviation using monthly returns for the composite and benchmark.
2. An additional 3-year ex-post risk measure if management feels standard deviation is inappropriate. The firm must match the periodicity of calculated returns used for the composite and benchmark.

Note that this standard deviation measure would be different from the internal dispersion measure that measures the standard deviation within the composite (relative to the average composite return). Recommendations for presenting relevant composite-level risk measures include: Standard 5.B.5. For each year that annualized composite and benchmark returns are reported, the corresponding annualized standard deviation of monthly returns for the composite and benchmark. Standard 5.B.6. Additional ex-post composite risk measures.

Although the recommendations do not suggest eliminating non-compliant data according to Standard 5.B.8, Firms should comply with the GIPS for all historical periods, this indicates firms should bring non-compliant data that is linked with compliant data into compliance.