iShares iBonds Dec 2036 Term Treasury ETF

The performance chart and period total return use a rolling window to the latest adjusted close. For 1M/3M/6M/... periods, default behavior is Yahoo-style rolling (first session on or after "latest date minus N calendar months" through the latest quote). If the calendar is already in a new month, the last quote is near month-end, and there is no current-month data yet, the window switches to N full calendar months ending in that quote month. Sharpe, Sortino, VaR and related metrics still come from the latest batch row. Sharpe/Sortino use annualized excess return versus the US risk-free rate, so a positive chart can still show a negative ratio if annualized return is below cash.