I am trying to map demographics data for a county in the UK based upon a combination of Census data. I want to compare the the averages for the county alone to the averages of the UK as a whole and display it using a sort of traffic lights symbology (red, orange, yellow, green, where red is way above average and green is way below average).
My problem is I'm not sure about what type of graduated symbology to use. Can someone please explain what Graduated Symbology is best to use in my situation?
I used Natural Breaks (Jenks) at first and was very happy with that but then I read on the ESRI website: "Natural Breaks (Jenks) are data-specific classifications and not useful for comparing multiple maps built from different underlying information." This makes me think using Jenks and then comparing the county averages to the national averages or comparing different categories (health data versus accessibility data) isn't appropriate.
So then I thought it would be best to use Equal Interval or Quantile symbology or define my own bands (split the results in four so I can assign colours to each 25%).
Any advice/help/information would be great.