Datasets

Data issues can occur in both historical and live data providers. Some common examples of data issues include the following:

• Missing or incorrect values
• Splits and dividends
• Listings and delistings
• Ticker changes

You can view a list of all the current data issues under the Data Issues tab in the community forum. Before you report a new issue, review the list of current issues to ensure that the issue is not already reported. The number of open data issues can sometimes be large, but our Data Team works on resolving them as quickly as possible while prioritizing the most important ones.

When all of the QuantConnect members report the data issues that they find, we can ensure the datasets are high quality for everyone. The easier it is for our Data Team to detect and reproduce the issues you report, the faster we can resolve them. If you encounter an issue with live data, email us a description of the issue. If you find an issue with the historical data of a dataset, follow these steps to report it:

1. Log in to the Algorithm Lab.
2. Open the Data Explorer Issues page.
3. On the Data Explorer page, fill out the form.
4. Follow these steps to attach a backtest or notebook that demonstrates the issue:
1. Click Attach Backtest.
2. Click the Project field and then select the project from the drop-down menu.
3. Click the Backtest field and then select the backtest from the drop-down menu.
5. Click Publish.