How to handle the missing value in the Scan function ?

[Inp]

data address2;
address = 's1,s2,,s3,s4, , ,j6';
var1=scan(address,1,',');
var2=scan(address,2,',');
var3=scan(address,3,',');
var4=scan(address,4,',');
var5=scan(address,5,',');
var6=scan(address,6,',');
var7=scan(address,7,',');
run;

proc print data=address2;
run;

output : 

Obs	address	var1	var2	var3	var4	var5	var6	var7
1	s1,s2,,s3,s4, , ,j6	s1	s2	s3	s4			j6

If this program is being running. Accourding to the data input , var 3 supposed to be missing value which I really expect. Can any one help? 

[Inp]

it is running on SAS9.4

[SASKiwi · Accepted solution]

Try adding the M modifier:

data address2;
address = 's1,s2,,s3,s4, , ,j6';
var1=scan(address,1,',','m');
var2=scan(address,2,',','m');
var3=scan(address,3,',','m');
var4=scan(address,4,',','m');
var5=scan(address,5,',','m');
var6=scan(address,6,',','m');
var7=scan(address,7,',','m');
run;

[Inp]

Thanks so much.