ETF Cost Model Methodology and Filing Source Boundaries

Our calculations separate assumptions from observed documents.

Updated October 16, 2026

Expense-ratio model: B(next) = (B + annual contribution) × (1 + return) × (1 − expense ratio).

Contributions arrive at the start of each whole year; expenses are simplified to annual deductions.

Actual fund accounting normally accrues expenses more frequently.

Total cost subtracts the modeled net balance from an otherwise identical zero-fee path.

Forgone growth can be negative in falling markets.

Ownership cost uses half the quoted spread and one commission at each end.

The fund comparison isolates annual fees and a front-end mutual fund load; taxes and distributions are zero in the current interface.

Withholding uses amount × yield, then sequential source-to-fund and fund-to-investor deductions; cumulative difference assumes fixed return drag, not individual tax advice.

Rates are user assumptions, not treaty determinations.

The SEC snapshot searches ETF across 485APOS, 485BPOS, N-1A and S-1 for October 1–16, 2026.

It retains primary documents in the first batch, not all search results.

Refresh retains the previous snapshot on failure; the historical window is fixed.

Document descriptions are not verified product names.

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Official reference: SEC Investor.gov: exchange-traded funds