Changes in Version 8.1-1

  o Updated documentation after R package "pwt9" was released
    for PWT 9.0.


Changes in Version 8.1-0

  o Update for PWT 8.1 (originally released in April 2015).
    It is an updated version of PWT 8.0, covering the same
    countries and period.


Changes in Version 8.0-0

  o New package pwt8 for PWT 8.x. So far only PWT 8.0 has
    been released (in July 2013) and has been added as
    pwt8.0.
