Sure, I can help you with that! To count the number of instances where people have ticked the boxes in a spreadsheet, you can use the COUNTIF function in Excel. Here's how:

1. First, select the range of cells that contain the tick boxes.
2. Next, click on the "Formulas" tab in the ribbon at the top of the screen.
3. In the "Function Library" section, click on the "More Functions" dropdown menu and select "Statistical".
4. From the dropdown menu, select "COUNTIF".
5. In the "COUNTIF" dialog box, you'll need to enter two pieces of information: the range of cells you want to count, and the criteria you want to use to count them.
6. For the range, simply click and drag over the cells that contain the tick boxes.
7. For the criteria, you'll need to enter the value that represents a ticked box. This will depend on how your tick boxes are set up. If they are checkboxes from the "Form Controls" menu, the value will be "TRUE". If they are checkboxes from the "ActiveX Controls" menu, the value will be "1". If they are simply cells with an "X" or a checkmark, the value will be "X" or "œ“".
8. Once you've entered the range and criteria, click "OK" to close the dialog box.
9. The COUNTIF function will now be displayed in the cell you selected, and will show the number of instances where the tick box criteria was met.

That's it! You can now use this formula to count the number of ticked boxes in your spreadsheet.