# Date/period specifiers

The period to cover can be specified with what this software package terms a datespec. It has the following legal forms:

yyyy-mm
  month mm in year yyyy
yyyy--ww
  week ww in year yyyy
yyyy-mm--dd
  a single day (day dd in month mm in year yyyy)
yyyy-mm-dd
  another form specifying a single day
epoch (literally)
  the entire period covering back to when data collection started.

Last modified: Tue Jun 17 15:33:05 MET DST 1997