CAD tip # 11898:

This table is then dynamically updated when you delete or add new blocks. The blocks are specified in the wizard, so their specification is stored in a DXE definition file. You can invoke the table update either manually (DATALINKUPDATE), or it is performed by default before the commands PLOT/PUBLISH, or you can add it by setting the DXEVAL variable also to the Save event.

You can schedule blocks, their layers, attributes or parameters and visibility states of dynamic blocks.

Using data extraction to create a counter is illustrated in the video:

The resulting value from this table can be then further linked to a specific property of other drawing objects (e.g. size) - see XLSparam - tip 11896 or referred (dynamically, see Insert>Expression>Cell) from a different table using a field/expression.