Problem: My data set is a hundred columns wide. In the Subtotal dialog, I have to click 6 columns, then scroll, click 6 more columns, then scroll. It is incredibly tedious. Having a "Select All" button would be incredibly helpful.
Strategy: Using the keyboard seems to be the fastest way. If you press the spacebar, the selected row will toggle from checked to unchecked. Scroll up, click on the words "Week 1" to select that row. Then, begin pressing spacebar, down arrow, spacebar, down arrow. It will still be tedious, but faster than using the mouse and scrolling.
- Individually click hundreds of checkboxes.