Rolling 250-Day Sharpe Ratio

This Pine Script indicator, “Rolling 250-Day Sharpe Ratio”, computes the trailing Sharpe Ratio for any traded asset over a 250-session window, equivalent to approximately one trading year. The script first derives daily log returns and adjusts them by subtracting the daily equivalent of the 3-month US Treasury yield to obtain the excess return. It then calculates the rolling mean and standard deviation of these excess returns to produce the annualized Sharpe Ratio, which is displayed as a continuous time series on the chart. This allows traders and analysts to assess how the asset’s risk-adjusted performance evolves over time relative to a risk-free benchmark.

A persistently high Sharpe Ratio can indicate strong risk-adjusted returns, but it is essential to approach extreme values with caution. Elevated Sharpe readings can sometimes reflect unsustainable trends, excessive leverage, or periods of unusually low volatility that may revert abruptly. Conversely, a low or negative Sharpe Ratio does not automatically imply an asset should be avoided; it might signal an opportunity if the risk environment normalizes.