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The U.S. Energy Policy Act of 2005, which the U.S. Congress 
passed on August 8, 2005, increases the number of days on which almost 
all the states in the USA will observe Daylight Saving Time (DST). 
Canada will also follow this protocol. 
 
Beginning in 2007, Daylight Saving Time will take effect on the second 
Sunday in March. This means that clocks are changed from 2:00 a.m. to 
3:00 a.m. on that day. DST ends on the first Sunday in November, when 
the clocks are turned back from 3:00 a.m. to 2:00 a.m. Previously, from 
1986 through 2006, DST began on the first Sunday in April and ended on 
the last Sunday in October. 
 
The changes in DST will have no effect on how the SAS® System runs. The 
information about whether SAS is running on Daylight Saving Time or 
Standard Time comes from the operating system. 
 
However, if your SAS program was written to make assumptions about these 
transitions, it might have to be changed. For example, the following 
program would sometimes produce incorrect results regarding 
DST in 2007: 
 
  data _null_; 
    current_datetime = datetime(); 
    current_date = datepart(current_datetime); 
    current_month = month(current_date); 
    if 5<=current_month<=9 then dst=1; 
    else if current_month^=4 and current_month^=10 then dst=0; 
    else do; 
      current_year = year(current_date); 
      startdate=mdy(4,1,current_year); 
      do while(weekday(startdate)^=1); startdate+1; end; 
      enddate=mdy(10,31,current_year); 
      do while(weekday(enddate)^=1); enddate=enddate-1; end; 
      dst=dhms(startdate,3,0,0)<=current_datetime<=dhms(enddate,2,0,0); 
        end; 
      if dst then put 'Currently in Daylight Saving Time'; 
      else put 'Currently in Standard Time'; 
  run; 
 
An example of code that calculates the beginning and ending dates for 
Daylight Saving Time for the years 2006 through 2009 is located at: 
 
  http://support.sas.com/kb/24/735.html  
 
Consult your System Administrator to find out whether the operating 
system on which your SAS software runs has been updated to recognize the 
changes in DST that begin in 2007. 
 
Foundation SAS uses the SAS private Java Runtime Environment (JRE), 
extensively. For information about recommended updates for JREs, 
including the SAS private JRE, see SAS Note  #019105 . 

Operating System and Release Information