You can compare multiple queries to generate a more complex chart. Note that the value for each category for comparison is refined by previous
selections in that group. For example, if the first category in a Group is "Denomination: Denarius", and Mint is select as the second category,
the drop-down menu will include only those mints that produced denarii. Add query
Alert: There must be at least one field in the group query.
Alert: There must not be more than one from or to date.
Alert: There must be at least one field in the group query.
Alert: There must not be more than one from or to date.
Alert: There must be at least one field in the group query.
Alert: There must not be more than one from or to date.