How to combin factorial split-plot experiment in sas? ( 2years expriment)

Hi

I am elementary user of sas, my experiment was 2 years agricultural experiment.
The experiment was laid out in the factorial split-plot arrangement based on a randomized complete block (RCB).

I can analysis of this experiment in one year by sas.

I know the script ( code) of it in sas:

"

data;
input a b c block y1;
cards;
;

proc anova;
classes block a b c;
model y1=block a b a*b block(a b) c a*c b*c a*b*c;
test h=a e=block(a b);
test h=b e=block(a b);
test h=a*b e=block(a b);
means a/duncan alpha=0.01 e=block(a b);
means b/duncan alpha=0.01 e=block(a b);
means c/duncan alpha=0.01;
means a*b a*c b*c a*b*c;
run;quit;


"

But my problem is the combine of 2 years.

does any body know the script ( code ) of it? can any body help me?