How to populate random missing values in a table withaverage of its preceeding and following values

[kk5]

Hi All,

I have a table with say 3 columns 1.Accno 2.month 3.Bal

What is required :

In this table i have records for each account where balance is missing for random months.(no of months considered : 24only)

What i needed is, to take the immediate next available balance , immediate preceeding available balance wrt the missing bal record, take an average of these values and populate this avg in place of the missing bal record.

table format :

Accno MOnth Bal

1         oct16   100

1         sep16   .

1.        aug16   50

As you can see, sep16 has a missing bal. so, avg(oct16 bal ,aug16) is 2 be populated in sep16 record.

Thankx in advance for any help!.

[Ksharp]

What if there are multiple series missing value ,what you gonna do ?



data have;
input Accno MOnth $ Bal;
cards;
1         oct16   100
2         sep16   .
3.        aug16   50
;
run;
data want;
 merge have have(keep=bal firstobs=2 rename=(bal=_bal));
 lag=lag(bal);
 if missing(bal) then bal=mean(lag,_bal);
 drop _bal lag;
run;