Investment analysis / Lump sum vs monthly
Lump sum vs. monthly investing
Compare investing the same budget all at once or every month over the selected period.
Two strategies, one budget
How the comparison works
Invest the entire cash balance on the first available trading day.
Invest equal monthly portions throughout the selected period.
Data sources and calculation rules
The 1st, 15th or last calendar day sets the monthly schedule. Dates before the effective start are skipped; non-trading dates move to the next stored trading day. Purchases beyond valuation remain cash. The total budget is divided by the installment count and is available from day one.
Uses the same stored split-adjusted daily closes as the asset backtest: Tiingo for US assets and KIS for Korean assets. The first available observation inside the requested period sets the start. Monthly dates use start-date anniversaries or the selected beginning/middle/end calendar dates; purchases use the next stored date, final valuation the last stored date inside the period.
Waiting cash remains in the input currency at 0% interest. Purchased holdings and trade remainders use the asset currency and historical USD/KRW when needed. Korean assets use whole shares; US assets allow fractional shares. Installments round down to two decimals and the last takes the remainder. Money uses HALF_UP to two decimals; KRW display rounds to whole won and USD to cents.
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