data a3_20;
input x@@;
time=intnx('quarter','01sep1971'd,_n_ -1);
format time date.;
cards;
63.2 67.9 55.8 49.5 50.2 55.4 49.9 45.3
48.1 61.7 55.2 53.1 49.5 59.9 30.6 30.4
33.8 42.1 35.8 28.4 32.9 44.1 45.5 36.6
39.5 49.8 48.8 29 37.3 34.2 47.6 37.3
39.2 47.6 43.9 49 51.2 60.8 67 48.9 65.4
65.4 67.6 62.5 55.1 49.6 57.3 47.3
45.5 44.5 48 47.9 49.1 48.8 59.4 51.6 51.4 60.9
60.9 56.8 58.6 62.1 64 60.3 64.6 71 79.4 59.9
83.4 75.4 80.2 55.9 58.5 65.2 69.5 59.2 21.5 62.5
170 -47.4 62.2 60 33.1 35.3 43.4 42.7 58.4 34.4
;
proc gplot data=a3_20;
plot x*time=1;
symbol1 c=red v=dot i =join;
proc arima data=a3_20;
identify var=x nlag=24 minic p=(0:8)q=(0:8);
estimate q=3 p=3;
forecast lead=20 id=time out=results;
proc gplot data=results;
plot x*time=1 forecast*time=2 l95*time=3 u95*time=3/overlay;
symbol1 c=black i=line v=star;
symbol2 c=red i=join v=none;
symbol3 c=green i=join v=none l=3;
run;