Yes, I have a suggestion for you to adjust the custom number formatting to display the numbers in the format you need.

You can modify the custom number formatting by adding a new condition to check if the number is less than 1 billion but greater than or equal to 1 million. If the number meets this condition, you can divide it by 1 million and display it with one decimal place followed by "Mil". Here are the steps to modify the custom number formatting:

1. Select the cell or range of cells that you want to format.
2. Right-click and select "Format Cells" from the context menu.
3. In the Format Cells dialog box, select the "Custom" category.
4. In the "Type" field, enter the following custom number formatting code:
   
   
   Code:

   [=1000000000] $#,###,, "Billion";[=1000000]$#,0.0, "Mil"; $#, "k"

5. Click "OK" to apply the formatting.

Now, when you enter a number less than 1 billion but greater than or equal to 1 million, it will be displayed in the format you need, with one decimal place followed by "Mil". For example, if you enter $1,965,532, it will be displayed as $2.0 Mil, and if you enter $1,838,928, it will be displayed as $1.8 Mil.