data ext;input x@@; y=log(x);z=dif(y);
t=intnx('year','01jan1949'd,_n_-1); format t year4.;
card;
1.44
1.79
1.88
2.17
2.06
2.38
2.42
3.03
3.41
4.85
5.61
6.34
6.09
5.53
5.54
6.14
6.29
5.68
5.73
5.26
6.08
6.59
7.08
7.88
8.52
9.27
10.56
10.92
11.49
12.43
13.98
15.69
17.19
20.32
24.01
30.35
37.10
43.16
53.27
68.66
85.92
91.73
110.69
149.64
194.37
260.66
366.20
458.57
552.14
625.85
679.23
746.10
840.01
956.12
1081.35
1229.62
1440.32
1649.20
1825.21
2160.48
2474.44
2881.08
;
proc gplot;plot x*t;symbol i=jion v=dot;
proc gplot;plot y*t;symbol c=black i=jion v=none;
proc gplot;plot z*t;symbol c=red i=jion v=none;
proc arima;identify var=z;
proc arima;identify var=z nlag=12 minic p=(0:6) q=(0:6);
estimate p=2;
forecast lead=3 id=t out=results;
proc gplot data=results;
plot z*t=1 forecast*t=2 l95*t=3 u95*t=3/overlay;
symbol1 c=blue i=none v=star;
symbol2 c=red i=jion v=none l=1 w=1;
symbol3 c=green i=jion v=none l=2 w=2;
run;