# I.6 - C54/C55 Analysis-Window Note

This is an internal methodology note, not City evidence.

C54 and C55 use an analyst-selected denominator window of March 17, 2023 through May 16, 2026 for the volume/authorship ratios. The window is pinned for consistency across the deck's quantitative denominator and should not be described as a City production date or a City-authored cutoff.

Calendar checks, exclusive day counts:

- March 17, 2023 to May 16, 2026: 1,156 days.
- March 20, 2023 to August 20, 2025: 884 days. March 20, 2023 is the first Lovato-authored entry in `I.1`.
- August 21, 2025 to May 16, 2026: 268 days. August 21, 2025 is the access-day entry in `I.1` and `M.035`.

The paper-volume totals remain sourced to `I.2`, `I.3`, and `I.5`; the authorship totals remain sourced to `I.1` and `I.2`; the identity-swap/residual-reason figures remain sourced to `I.4`.