data rdu;  do i=1 to 7; input year @; end;
do mon = 1 to 12; input month $ @;
do y=1 to 7; year=1994+y;
input passengers @; pass=.; passengers=passengers/100000;
if date <'01sep01'd then pass = passengers;
date=mdy(mon,1,year); format date monyy.;
output; end; end;
do mon = 1 to 12;
do y=8 to 9; year=1994+y;
passengers = .; pass=.; month=" ";
date=mdy(mon,1,year); format date monyy.;
output; end; end;
cards;
            1995     1996      1997     1998     1999      2000    2001
January   473866   438769    444273   604342   525949    588991  769132
February  452978   495525    488746   484586   541346    723692  748445
March     496525   577078    594879   474051   676799    904590  934275
April     496668   568622    578303   619307   717688    910042  962570
May       483988   601281    597733   629110   716144    943408  936657
June      490760   572415    580874   626209   832487    960126  996445
July      501678   546671    585606   660466   877412    981588 1034162
August    530381   537172    584438   629912   823848    922491  891104
September 464065   442677    518738   569238   699273    800379  454679
October   528141   571488    615449   666858   871891    928389  624452
November  519052   521129    569094   640275   855823    907360       .
December  499033   545044    566741   615831   803115    867329       .
;
proc sort; by date;
data RDU; set RDU;
if date > '31aug01'd then X=.994**(date-'01sep01'd);
else X=0;
proc reg noprint; model passengers=date X; output out=outreg
P=Preg;
proc glm noprint; class mon;
  model passengers=mon date X/solution;
  output out=out1 predicted = p L95=L U95=U;
  proc print data=out1 (firstobs=80 obs=85);
  var p pass; run;
data out1; set out1; if passengers>0 then do; L=.; U=.; end;
goptions reset=all;
* goptions targetdevice = pscolor;
%macro arrow; 
  SS=size; size= 2; XX=X+8; YY=Y; 
  alpha= atan(-1*slope/AR); put @20 "Using alpha = " alpha; 
  X=xx -r*cos(alpha+theta); Y=YY-AR*r*sin(alpha+theta); output; 
  X=XX -r*cos(alpha-theta); Y=YY-AR*r*sin(alpha-theta); output; 
  X=XX; Y=YY; output;  size=ss; 
  %mend; 
data anno;
 drop XX YY; 
 Xsys="2"; YSYS="2";         
 theta=.4; r=120; 
 AR=(1300000-300000)/('01jan04'd-'01jan95'd);
 *aspect ratio*;

 function = "label";
 Text = "    Sept. 11, 2001"; color="black";
 position='5'; size=1.5; style="centB";
 X='01jan99'd; Y =1200000; output;
 function="move"; X='01jul00'd; output;
 function ="draw";  X='01sep01'd; size=4; output;
  slope=0; %arrow;
  
 function = "label";
 Text = "Actual"; color="red";
 position='2'; size=1.6; style = "centB";
 X='01jan97'd; Y = 900000; output;
 function="move"; X='01jan97'd; output;
 function ="draw"; Y=824000; X='01oct98'd; size=4; output;
 X='10may99'd ; output; 
 slope = 0; %arrow;

 function = "label";
 Text = "Model"; color="blue";  position='2'; size=1.6;
 style="centB";
 X='01jan97'd; Y = 800000; output;
 function="move"; X='01jan97'd; output;
 function ="draw"; Y=724000; X='01aug97'd; size=4; output;
 X='01may98'd; output;  %arrow;

 function = "label";
 Text = "Prediction" ; color="green";  position='2'; size=1.6;
 style="centB";  
 X='01jan03'd; Y = 430000; output;
 position=5; Text= "Intervals"; output; 
 function="move"; X='01mar00'd; output;
 function ="draw"; Y=3400000; X='01aug03'd; size=4; output;
 X='01aug04'd; output;  %arrow;
  
 data anno; set anno; Y=Y/100000; 
proc gplot; plot Y*X; 
 proc print data=anno; run; 
proc gplot annotate=anno data=out1;
plot (preg p passengers L U )*date/overlay href='11sep01'd vaxis=axis1;
symbol1 v=none i=join w=4 c=black;
symbol2 v=dot  i=join w=4 c=blue;
symbol3 v=none i=join w=4 c=red;
symbol4 v=none i=join w=4 c=green r=2;
title "Passengers at RDU Airport";
axis1 label=(rotate=0 angle=90 font=centb height=1.5); 
label preg ="Passengers x 100,000";
run;