Yes, what you are describing is called a "Grouping" function in Excel. It allows you to collapse and expand rows or columns to show or hide details. Here's how you can create roll-up rows in Excel:

1. Select the rows that you want to group together.
2. Right-click on the selected rows and choose "Group" from the drop-down menu.
3. A small box with a plus sign (+) will appear to the left of the first row in the group.
4. Click on the plus sign (+) to collapse the group and hide the rows.
5. The plus sign (+) will change to a minus sign (-) indicating that the group is collapsed.
6. Click on the minus sign (-) to expand the group and show the hidden rows.
7. The minus sign (-) will change back to a plus sign (+) indicating that the group is expanded.

You can also use the keyboard shortcut "Alt + Shift + Right Arrow" to group rows and "Alt + Shift + Left Arrow" to ungroup rows.

In addition, you can customize the appearance of the grouping symbols by going to "File" "Options" "Advanced" "Display options for this worksheet" and checking or unchecking the "Show outline symbols if an outline is applied" box.