Technical Studies Reference

Percent Change Since Open

This study calculates and displays the difference between the last trade/Closing price of the bar and the Opening price of the trading day, as a percentage. The specific value being used for the calculations can be changed in the Input Data setting.

The time of the Opening bar of the trading day is determined from the Session Times for the chart.

Through the Start Time Input, it is also supported to calculate the percent change since the opening price of the first bar in the chart by setting it to First Bar in Chart. Therefore, by controlling the starting Date-Time in the chart, you can calculate the percentage change since a particular Date-Time. For further details, refer to the Start Time Input description.

At the chart bar which is the opening bar for the trading day, the percentage difference between the closing price of that bar and the opening price of that bar is calculated and displayed. Therefore, at the very first bar of the day, the percentage difference is not necessarily going to be zero.


  • Start Time: By default this is set to Trading Day Start Time which means that the opening price is the opening price at the start of the trading day as set through the Session Times in Chart >> Chart Settings.

    If this is set to First Bar in Chart, the opening price used for the percentage calculation is the opening of the first bar in the chart and it does not change from day-to-day.

    Through Chart >> Chart Settings, you can control the starting date in the chart or how many days to load in the chart to control the opening price when using First Bar in Chart. Refer to Use Date Range >> From / To.
  • Input Data: This controls what data is used for the calculation. Whatever value is chosen for this input will be the value used both for the current bar and for the opening bar of the current day. For example, if this is set to High, then the High of the current bar is compared to the High of the opening bar of the current day.

    Note that setting the Input Data to either Open or Last will give the same calculation, which is the comparison of the Last price of the bar and the Opening price of the trading day. All other settings will use the Input Data setting for both the current bar and the opening bar.

Percent Change for Different Symbol

In order to show the Percent Change Since Open on a single chart for multiple symbols, follow these instructions:

  1. On the Chart in which this study is displayed, add the Add Additional Symbol study to add as many additional symbols to this chart as needed. If it is not necessary to see the symbol data itself for these additional symbols, then select the Hide Study button for each of the Add Additional Symbol studies.
  2. Add the Percent Change Since Open study to the main chart.
  3. Select the Settings button for the Percent Change Since Open study and change the value in the Based On selection box to the desired symbol. See Basing a Study on Another Study for more information.
  4. Change the value in the Chart Region selection box as desired to place the graph in an appropriate location on the chart. See Chart Region for more information.
  5. Repeat steps 3-4 as necessary.
  6. Select OK to close the Settings window.
  7. Select OK to close the Studies window.

*Last modified Wednesday, 08th August, 2018.