Time Series with 2020 Geographic Integration

We do plan to release time series standardized to 2020 geographies eventually, but we haven’t set a timeline and have no immediate plans, so no, not in the next month.

Until then, my top recommendation would be to use time series standardized to 2010 if possible. If not, yes, you can use our crosswalks from 2010 to 2020 units to standardize to 2020.

If you also need 1990 and 2000 data for 2020 units, it’d be reasonable to start with our 1990 and 2000 data standardized to 2010 block groups, and then use one of our crosswalks from 2010 block groups to 2020 units to allocate the 1990 and 2000 estimates to 2020 units. The primary issues with this approach are that:

  1. Starting from block group estimates is not as accurate as starting from blocks
  2. In cases where a 2010 block group intersects multiple source 1990/2000 zones and multiple target 2020 zones, this approach would inevitably allocate some data from source zones to target zones in cases where there is in fact no overlap among the zones. (I discuss this problem in detail in this discussion of “indirect overlay” in the context of interpolation from 1990 blocks to 2010 units.) It’s better to take account of actual spatial relationships between 1990/2000 zones and 2020 zones (e.g., by using constrained direct overlay and cascading density weighting). That’s what we intend to do in constructing our time series standardized to 2020 units, and that added complexity is one reason why it may be some time before we complete that work.