Purpose – To create a variable point symbol map of the State of Oregon, where the distribution of Vacant Housing Units are depicted.

 

Method – The projected coordinates were set to Contiguous Albers Equal Area Conic for the cartographic boundary file and corresponding attribute data from the United States Census Bureau.

 

Each county polygon was then converted to point data, where Graduated Symbols was chosen as the type of map.

 

Vacant units attribute fields were selected, with five classes and the Natural Breaks classification method.

 

A well-balanced figure (symbols) - ground (map) contrast was used using the CMYK colour model of complementary colors of yellow and purple. To create a set of symbol sizes that enhanced the spatial distribution being mapped, the circle sequence sizing was 73.44, 54.72, 35.28, 24.48 and 15.84.

 

The legend was then converted to graphics and manually rearranged by ungrouping all the objects into single elements. The legend was then rearranged using generous number of temporary guides to align everything. A vertical and horizontal distance of 0.1 was used between the labels and circles.

 

Next, the scale bar units were set to rounded Kilometers and used two divisions, with a division value of 20 km and two subdivisions.

 

Lastly, a neutral colour was added to the background of the data frame of 8% grey.