Geographical distribution
This page will show the distribution by postal areas or districts, that’s the bit of the postcode before the space - CA12, etc.. Either select a year from the drop down box or if the repeat box is checked then the code will loop through every year from 1960 (skipping over the years with no completions), each year is visible for a couple of seconds.
- Areas are indicated by the leading letters in the postcode, so: “M“, “CA“, “NE“ and so on.
- Districts are sub-divisions of Areas, they equate to the location of the delivery office, so: “M16“, “CA12“, “NE2“ etc.
There are 124 postal areas and nearly 2900 postal districts meaning the former are easier to distinguish on the chart at typical screen sizes. However for rural codes they cover large areas so may not be precise enough. Showing the data by area is also quicker - there’s 25 times fewer things to calculate.