drill-down
Reports that display all their data at once may not be convenient to
use. With drill-down you can display an overview of the data but give users the ability to
reveal further layers of data as required. For example, one user may be interested in seeing
sales of a particular product group or individual product in all years. Another may be
interested in seeing sales of all products in a particular quarter or month. Each user can
drill-down through the products or years to see only the data they require. You drill-down
by expanding and collapsing the tree structures of the lists containing the data.