The Sashelp.ENSO (El Niño–Southern Oscillation) data set contains measurements of monthly averaged atmospheric pressure differences between Easter Island and Darwin, Australia, for a period of 168 months. These pressure differences drive the southern trade winds. This data set is used to illustrate fitting nonlinear functions to a scatter plot by using methods such as loess and penalized B-splines. These data show both seasonal variations and variations due to El Niño. The following steps display information about the Sashelp.ENSO data set and create Figure B.6:

title 'El Nino Southern Oscillation Data';
proc contents data=sashelp.ENSO varnum;
   ods select position;
run;

title 'The First Five Observations Out of 168';
proc print data=sashelp.ENSO(obs=5);
run;