Here's how to use conditional formatting with formulas for dynamic data highlighting in Excel:

1. Select the data range you want to format.

This is the area where you want the conditional formatting to be applied. Make sure it includes the header row if you want to use cell references in your formula.

2. Go to Conditional Formatting and choose "New Rule."

You can find the "Conditional Formatting" option under the "Home" tab in the Styles group. Clicking on the dropdown arrow will reveal "New Rule."

3. Choose "Use a formula to determine which cells to format."

This option allows you to create a custom rule based on a formula.

4. Enter your formula in the "Format values where this formula is true" box.

This is where the magic happens! Here are some examples of formulas for dynamic highlighting:

* Highlight values greater than a specific number: `=A1>100` (Replace A1 with your actual cell reference for the starting value). This formula will highlight any cell in the selected range where the value is greater than 100.
* Highlight cells containing text: `=ISTEXT(A1)` (Replace A1 with your cell reference). This formula will highlight any cell containing text data.
* Highlight cells with duplicate values: `=COUNTIF($A$1:$A1,A1)>1` (Replace A1 with your starting cell reference). This formula will highlight cells with duplicate values based on the column you apply it to.
* Highlight cells based on another cell's value: `=A1=$B$1` (Replace A1 and B1 with your cell references). This formula will highlight cells in your selected range that match the value in a specific cell (B1 in this case).

5. Click "Format" to choose the highlighting style.

Here you can define how you want to highlight the cells that meet your formula condition. You can choose from various options like font color, fill color, borders, etc.

6. Click "OK" to apply the conditional formatting rule.

Now your data will be dynamically highlighted based on the formula you defined. As you add or modify data in your spreadsheet, the formatting will automatically adjust to reflect the changes.

Tips:

* You can use various logical operators (AND, OR, NOT) within your formulas to create more complex highlighting rules.
* Use absolute cell references ($A$1) when referencing a specific value you want to compare against throughout the formula.
* Conditional formatting can be very powerful, so experiment with different formulas to achieve the desired highlighting for your data.