Here is your biannual daylight savings message:

Once upon a time, my colleague Paul Fischbeck and I made some quick calculations about the changes in pedestrian risks associated with daylight savings.  They were a lot bigger than we thought they would be. The moral of the story — watch yourself crossing the street, especially when it’s dark outside.

There are some interesting regulatory policy implications of the time change. If you are interested, here are my thoughts posted at the Organizations & Markets blog a few years back.