SAS iterpolation : alternative to proc expand

Question

From annual data :

I would like to create the the data per day but I can't use the proc expand because the SAS ETS is not available.

Thank you for your suggestions.

Answer 1

Something like this is a basic approach perhaps:

• create a list of dates for interpolation
• merge have data (shown above, not included in code below)
• Plot to see if linear pattern, (looks somewhat exponential/curved)
• run linear regression, saving predicted values
• plot interpolated values against actual values

data years;
do date='30Jun2017'd to '30Jun2022'd;
output;
end;
run;



data have;
merge years have;
by date;
format date date9.;
run;

proc sgplot data=have;
series x=date y=px_last;
run;

proc reg data=have plots;
model px_last = date;
output out=pred p=predicted_value;
run;

proc sgplot data=pred;
series x=date y=predicted_Value;
scatter x=date y=px_last;
run;