Replicate excel "forecast.ets" in SAS

[LFern]

Hello 🙂 I have this data:

interval	sales
1	2,564,303,150
2	2,549,961,650
3	2,505,588,400
4	2,657,071,900
5	2,661,563,300
6	2,710,006,000
7	2,576,194,550
8	2,747,461,050
9	2,695,094,300
10	2,755,230,050
11	2,623,167,350
12	2,850,129,800
13	2,849,498,000
14	2,947,182,650
15	2,629,371,850

On excel, "=FORECAST.ETS(A17,B2:B16,A2:A16,,,)" achieves the following result:

Interval	Sales
16	2,917,825,906

However, when I forecast on SAS, I achieve a different result:

data have;
input interval sales;
datalines;
1	 2564303150 
2	 2549961650 
3	 2505588400 
4	 2657071900 
5	 2661563300 
6	 2710006000 
7	 2576194550 
8	 2747461050 
9	 2695094300 
10	 2755230050 
11	 2623167350 
12	 2850129800 
13	 2849498000 
14	 2947182650 
15	 2629371850 
;


proc forecast data=have lead=1
method=expo trend=3
out=pred outfull outresid;
var sales;
id interval;
run;

SAS forecast result:

16	2880043215.5

How do I modify the SAS code to replicate excel's forecast for interval 16 ($2,917,825,906 sales)?

Any help is appreciated, thank you.

[sbxkoenk]

First of all,

PROC FORECAST is obsolete and is no longer part of the documentation (SAS 9.4 M7).

This is what you get when submitting PROC FORECAST in SAS 9.4 M7 (Maintenance Level 7) :

proc forecast; run;

WARNING: The FORECAST Procedure is obsolete. You may continue to use PROC FORECAST but this is
not recommended. For time series forecasting, consider using newer procedures such as
the ESM Procedure, the UCM Procedure, or the ARIMA Procedure.

Hence, try PROC ESM !

ESM optimizes the smoothing weights ( and PROC FORECAST does not !! )

Or better, try to find out what Excel is exactly doing and tell us, because there are dozens of possible algorithms that can be applied of course ! Only Exponential Smoothing already has about ten flavors.

Thanks,

Koen