Asset Log · Sources and verifiable data
Data analysis methodology
These methods keep index, actual-fund and reference series distinct and make calculation conditions traceable.
Define the series
Record provider, index or fund, price or total return, gross or net, currency, FX hedge, live or backtest, and start/end dates. A fund includes expenses and tracking differences. A JPY purchase does not remove foreign-exchange risk. Different conditions must not be joined without a clear label.
Sources and acquisition
Prefer index administrators, managers, regulators and exchanges. Product pages, prospectuses, monthly reports and CSVs serve different purposes. Record source URL, retrieved_at, data_as_of, file size, row count and SHA-256. A hash identifies bytes; it does not prove the data are true. If a provider revises historical CSV data, preserve both acquisition records and recalculate.
Prepare the data
Sort dates and check duplicates, missing periods, nonpositive values, columns and units. Month-end means the last available business-day observation, not an interpolated holiday price. Reference data used to fill gaps must remain separate from the live fund history.
Return definitions
Monthly return = P(t) / P(t−1) − 1. If the preceding observation is absent, leave the result blank. Calculate with unrounded data. A completed annual return compares consecutive year-end observations; the launch year is not invented as a full year. An incomplete year carries a YTD cutoff.
CAGR = (P1 / P0)^(365.2425 / d) − 1, where d is elapsed calendar days. Annualized volatility is the sample standard deviation of monthly returns × √12, with sample size disclosed. Volatility includes upward moves. Maximum drawdown scans the daily series for the largest decline from a preceding peak and records peak, trough and recovery dates; an unrecovered decline stays labeled unrecovered.
Illustrations and comparisons
A lump-sum example purchases the same series at its stated starting date. Regular contributions accumulate units at the stated purchase prices. Disclose taxes, rounding and purchase/redemption costs; separate starting capital, ending value and gain. These are not personal results or forecasts. Comparisons align actual funds, currency, return type and common dates. A short common history is a limitation, and a CAGR ranking is not a permanent judgment.
Validation and updates
Check CSV rows, date range and endpoint values; independently recalculate returns, drawdowns and examples. Compare published tables with calculation records. Missing source, cutoff, retrieval record or input hash blocks the relevant publication check. Monthly updates reacquire source files, check revisions and recalculate the period. Material numerical or methodological corrections are logged. Each article must still explain its own series, period, assumptions and index-specific rules.
Source page updated: 2026-09-03. Localized edition reviewed: 2026-09-11. This describes methods, not individual financial advice.