data A;
input acct sales;
cards;
1 23
1 33
1 54
2 32
2 34
;run;
data b;
  retain point 1;
  if _N_ < nobs then do;
    point = point + 1;
    set a point=point nobs=nobs;
    lead= sales;
  end;
  set a end=end;
run;
proc sort data=b;by acct;run;
data b;set b;by acct;
if last.acct then lead=.;run;

PROC SORT DATA=A;
  BY acct DESCENDING sales;
RUN;

DATA B;
  SET A;
  BY acct DESCENDING sales;
  sales2=lag(sales);
  if first.acct then sales2=.;
RUN;

PROC SORT DATA=B;
  BY acct sales;
RUN;

楼上可以测试下面的数据
1 23
1 33
1 54
2 32
2 34
2 32

可以这样

data A;
input acct sales;
count+1;
cards;
1 23
1 33
1 54
2 32
2 34
2 32
;

PROC SORT DATA=A;
  BY acct DESCENDING count;
RUN;

DATA B;
  SET A;
  BY acct DESCENDING count;
  sales2=lag(sales);
  if first.acct then sales2=.;
RUN;

PROC SORT DATA=B;
  BY count;
RUN;

data b;
  set b;
  drop count;
run;

Here is the one with simple logic.

1512  data need;
1513    set a end=end;
1514    by acct;
1515    n=_n_+1;
1516    if end=0 then set a (keep=sales rename=(sales=sales2)) point=n;
1517    if last.acct then sales2=.;
1518
1519
1520  run;

NOTE: There were 5 observations read from the data set WORK.A.
NOTE: The data set WORK.NEED has 5 observations and 3 variables.
NOTE: DATA statement used (Total process time):
      real time           0.00 seconds
      cpu time            0.00 seconds
1521
1522  proc print; run;

NOTE: There were 5 observations read from the data set WORK.NEED.
NOTE: PROCEDURE PRINT used (Total process time):
      real time           0.00 seconds
      cpu time            0.00 seconds

  Obs    acct    sales    sales2

   1       1       23       33
   2       1       33       54
   3       1       54        .
   4       2       32       34
   5       2       34        .