Flashback is a new member of the Stockfuse family. It is a simple app that lets you backtest trading strategies. Enter a few positions and hit “Run,” Flashback crunches the numbers and provides detailed historical return and risk analytics, allowing you to make more informed investment decisions.

Frequently Asked Questions

What’s the difference between shares and percent?

Flashback allows you to enter quantity either in number of shares or as percentage of overall portfolio. In the “shares” mode, entering “20” indicates you’d like to hold 20 shares of a stock. In the “percent” mode, entering “20” means the position has a weight of 20% in your backtest portfolio.

What happens if my percentages do not add up to 100%?

Cash is automatically added. For example, if the weights of your positions (in percent mode) add up to 80%, we’ll automatically add a 20% cash position. If the weights add up to 120%, we’ll include a -20% cash position (i.e., we assume the portfolio is 1.2x levered).

Why do the returns differ so much from Yahoo and Google?

Flashback always reports total returns, which includes dividend reinvestments and other corporate actions. By contrast, the percentage returns provided by Yahoo and Google are price returns only and understates actual investment performance.

Can I include indices in my backtest?

Yes, when entering your position, type . (period) to see a list of supported total return indices. Our researchers have compiled a number of long-term indices specifically for Flashback:

  • .ACTR: A total return index measuring the performance of the US stock market, including all shares traded on NYSE and NASDAQ.
  • .TSY: A total return index measuring the performance of the US Treasury (government bond) market.
  • .TIPS: A total return index measuring the performance of US TIPS (Treasury Inflation-Protected Securities). This includes simulated returns calculated by our researchers before 1997.
  • .CORP: A total return index measuring the performance of the corporate bond market.
  • .DWTR: A total return index measuring the performance of developed world stock market (returns are in USD).

Is my portfolio rebalanced?

Portfolios are only rebalanced if 1) there are no short positions and 2) quantities are entered as percentages. If both conditions are met, positions are rebalanced monthly.

What happens if I short a stock and the share price rise by more than 100%?

We assume that your return is -100% (i.e., complete loss of capital) and no further returns will be calculated thereafter.


Market data provided by Xignite, BATS BZX Real-Time Price, and SIX Financial Information.

Important Disclaimers

Hypothetical or simulated results have certain inherent limitations, including among others, that the results do not represent actual trading performance, the performance may have been realized with the benefit of hindsight. Further, past performance is no guarantee of future results.

We utilize data from many sources. Some information generated internally may be theoretical in nature. External data are obtained through Xignite. While we consider information from external sources to be reliable, we do not independently verify information obtained from external sources and we make no representation or warranty as to the accuracy, completeness or reliability of such information.

The information provided herein is not intended to provide a sufficient basis on which to make an investment decision and investment decisions should not be based on simulated, hypothetical or illustrative information that have inherent limitations.