COMMENTARY
I have observed from very early in my career that an 'average is always wrong' ... almost all, if not all, the data points are going to be different from the average, some will be above, some will be below'. Understanding the detail points makes it possible to expand things that are good and reduce or eliminate things that are bad. The result of this is for the 'average to change'. A policy decision that has its origin merely in pushing on the [non-existant] average will work less well.

Since this graphic was drawn in 2008, there have been massive improvements in the power of data analysis systems ... but the underlying concept of decision making based on detail not average remains the same.
Peter Burgess

Illustrating the idea that national level and community level data are similar

This is a simple graphic to illustrate the idea that national level and community level data are similar ... with one set of data useful for showing the aggregate situation and performance, and the other for understanding how one community is doing relative to others.

The national aggregates are useful to show progress ... but very much less useful in deciding exactly what decisions are going to be best for any specific community.

With modern data analysis, the decisions made have the potential to be an order of magnitude better than those based on the old fashioned aggregates. The problem with modern decision making is that much of the big policy making remains mired in old-fashioned methodologies. This has to change.