A combo visual has the following shelves:
This is conceptually the X axis. Use a Dimension field to create bars and lines/areas for aggregate values in this dimension.
This shelf accepts a single field.
This is conceptually the Y axis. Use a Measure field from the Data menu to display aggregate values as bars.
This shelf accepts a single field.
This is conceptually the Y axis. Use a Measure field from the Data menu to display aggregate values as lines or areas.
This shelf accepts a single field.
This is conceptually the Y axis. Use a Measure field from the Data menu to highlight aggregates of this measure.
This shelf accepts a single field.
Add Measure fields from the Data menu for additional information in the graph's Tooltip.
This shelf accepts multiple fields.
Add Dimension or Measure fields from the Data menu to include or exclude categorical or value criteria.
This shelf accepts multiple fields.