Dear @Anne Osterholz,
I understand how frustrating it is when table formatting doesn't automatically apply to new rows or columns. This typically occurs because the shading was applied as a manual format override rather than being defined within the Table Style.
To fix this and ensure consistent formatting, please follow these steps:
Option 1: Apply Formatting via Table Style Options
Instead of using the "Shading" bucket tool on specific cells, use the built-in style engine:
- Click inside your table to reveal the Table Design tab.
- In the Table Style Options group (left side), ensure Banded Rows or Banded Columns is checked.
- New rows will now automatically inherit the alternating shading pattern.

Option 2: Modify the Table Style
If you are using a custom color scheme, you must bake the shading into the style itself:
- Right-click the table style you are using in the Table Styles gallery and select Modify Table Style.
- In the "Apply formatting to" dropdown, select Header row, Odd numbered rows, or even numbered rows.
- Choose your desired background color.

- Select the radio button new documents based on this template at the bottom if you want this to persist in future files.
- Click OK.

Option 3: Clear Manual Formatting
If the steps above don't work, existing manual formatting might be "blocking" the style.
- Highlight the entire table.
- Go to the Home tab and click Clear All Formatting, then re-apply your desired Table Style.
For more detailed information on managing these settings, you can refer to the official Format a table - Microsoft Support
I hope this helps resolve the issue immediately. Please let me know if you need further assistance.
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