How to set the validity period of Tongda letter stock selection formula

The validity period of Tongda letter stock selection formula can be set by the following steps:

1. Open the communication software and enter the user-defined indicator interface.

2. In the user-defined indicator interface, find the stock selection formula for which the validity period needs to be set, right-click the formula and select Edit Indicator in the pop-up menu.

3. In the "Edit Indicator" interface, find the "Validity Period" option, click to select the validity period of the formula, and you can choose "Effective Today", "Permanent Validity" or user-defined validity period.

4. If you select a custom validity period, you can set the start date and end date of the formula in the custom validity period option.

5. After the setting is completed, click OK to save the setting.