# Square-root-of-time and autocorrelation

My question is that when we have autocorrelation in daily volatilities can we scale daily volatility to annual basis using square-root-of-time rule?

Does it breach the main assumption of the rule that says volatility is constant across period? Thank you

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There was some confusion from my side. You ask about autocorrelation in volatility (which is a stylized fact in financial time series) and not about autocorrelation in returns thermselves-right? My answer was about autocorrelation in returns. I would alter/delete my answer. –  Richard May 12 at 14:26