So how good are Population Projections?

If you are using population projections that are publicly available, chances are you’re using the Texas State Data Center (TXSDC) as your resource. They’ve got several projection scenarios available and other planning organizations like the Capital Area Metropolitan Planning Organization utilized a modified version of two of their scenarios for the 2035 transportation plan.

How do the estimates compare to the projections? Well, the Census Bureau released population estimates yesterday for counties and if you compare those numbers to the projection made by TXSDC using the Scenario 3.0, then that projection was off only 2.1%.

So what does that mean, are we growing 2.1% faster than we were from 2000-2007?

Maybe, but the Census Bureau and the TXSDC use slightly different methodologies that could attribute for some of the difference. But, still 2.1% is pretty good, I think.

Here’s a look at this data for CAPCOG counties:

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Hays, Caldwell, and Williamson are pretty much dead on. The rural areas seem not as accurate, but I think that might be due more to the methodological differences.

So what will we look like in 10 years based on those projections. Population for the region would be 2.37 million, which is over 550K more than current population estimates.

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Of course all this assumes the population estimates are accurate. I guess we’ll have to wait until the Census 2010 data is released in April 2011 to see how we really measure up.

Chris Ramser