Placement
In most cases the map element or elements will consume the majority of the layout
space. When there is a hierarchy of maps on the same layout there should be no
doubt as to which is the main map. It is either set apart in size or position or, most
effectively, both. When just one map is desired it is placed in a central but slightly
off‑center location on the layout. (If you have multiple time series maps, they are
usually all of the same size and shape, and when put together they function similarly
to a single large map in terms of layout placement.) Does this mean that you have to
conform to this convention? Not necessarily, but make sure you have good reason
not to. For example, there are layouts that contain a centered map with, say, logos