title "Oil production";
data oil;
infile "C:\Documents and Settings\rsettimi\My Documents\Courses\CSC423\Lecture Notes\Week5\oilproduc.txt";
input  year oil;
label oil = "Oil production in millions of barrels";
ylog=log(oil);
label ylog="log of oil";
/*
data before;
set oil;
if year > 1970 then delete;
data after;
set oil;
if year<=1970 then delete;
*/

proc gplot;
plot oil*year;
plot ylog*year;
run;
* Regression analysis;
* to estimate the rate of lean increase per year;

proc reg;
model ylog=year;
plot ylog*year;
plot ylog*year;
plot residual.*year;
plot student.*year;
plot npp.*residual.;
run;