Yes, you can use the Subtotal function with an If criteria to sum only the values in column B where column C is equal to Y. Here's how:

1. Click on cell B8 where you want to display the subtotal.
2. Type the following formula:
   Code:

   =SUBTOTAL(9,IF(C2:C6="Y",B2:B6))

3. Press Ctrl+Shift+Enter to enter the formula as an array formula. This will ensure that the formula calculates correctly.
4. The subtotal will now be displayed in cell B8, and it will only include the values in column B where column C is equal to Y.

Note: The IF function checks each cell in column C to see if it contains the value "Y". If it does, the corresponding value in column B is included in the subtotal. If it doesn't, the value is excluded from the subtotal. The SUBTOTAL function then calculates the sum of the included values.