Long term trend in number of homes sold

The web site Trulia.com provides a chart showing the longer term number of home units sold trend. Unfortunately, the chart uses a logarithmic scale for the Y-axis, which greatly distorts the chart.

Here’s the original Trulia.com chart for Spokane:


Here is a version of the chart converted to show the trend, but using a linear Y-axis, making it easy to see the true trend over time. Not shown on the X-axis, below, are the years 2000 to 2014, corresponding to the X-axis shown above. The chart below, ends at the low point for 2014. Obviously, the number of homes sold will increase through the spring and summer.


The second chart was made by converting the original data chart into numeric values, using a program that extracts approximate data points from charts. The extracted data points are used in a spreadsheet program to redraw the chart or perform other analysis.   The conversion produces values that are close to the original but it is not possible to recover the exact data used in the original chart. However, the approximation produces a valid summary of the long term trend. It is assumed this refers to the number of homes old per month, but Trulia does not specify.

This chart was created in response to several questions received about the current real estate market.


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