费用分类汇总程序求助，^_^

有以下表格数据，

caseID	Entdat	hoscost
260754	1950-3-31	62973.59
277270	1950-12-23	136719.83
277270	1951-2-27	95801.55
277270	1952-5-22	54787.56
277270	1952-10-5	163104.40
280785	1951-2-28	83876.28
280785	1952-6-23	157131.43

我想构建一个新库，算法如下：
1、同一caseID，如果有多次住院记录，按照入院时间（Entdat）排序后，除首次住院外，计算每次入院时间与首次入院时间之差Suryear，以年为单位。
2、如果Survyear>1，定义1年以内的住院花费之和为FirCost，1年以内的住院次数为FirNumHos；1年之后的住院花费之和为ConCost，1年之后的住院次数为ConNumHos；
3、计算同一caseID总的住院次数（TNumHos）和总的住院花费（Thoscost）

最终应该得到的数据表如下：

caseID	Thoscost	TNumHos	FirCost	FirNumHos	ConCost	ConNumHos
260754	62973.59	1	62973.59	1	0	0
277270	450413.34	4	232521.38	2	217891.96	2
280785	241007.71	2	83876.28	1	157131.43	1

data a;
input caseID $        Entdat yymmdd10. hoscost $;
format Entdat yymmdd10.;
cards;
260754 1950-3-31 62973.59
277270 1950-12-23 136719.83
277270 1951-2-27 95801.55
277270 1952-5-22 54787.56
277270 1952-10-5 163104.40
280785 1951-2-28 83876.28
280785 1952-6-23 157131.43
run;
proc sort data=a;
by caseID Entdat;
run;

data out;
set a;
by caseID;
retain firstdate Thoscost TNumHos FirCost FirNumHos ConCost ConNumHos;
if first.caseID then firstdate=Entdat;
if Entdat-firstdate<365 then tag=1;else tag=2;
if first.caseID then do;
Thoscost=0;
TNumHos=0;
FirCost=0;
FirNumHos=0;
ConCost=0;
ConNumHos=0;
end;
Thoscost+hoscost;
TNumHos+1;
if tag=1 then do;
FirCost+hoscost;
FirNumHos+1;
end;
if tag=2 then do;
ConCost+hoscost;
ConNumHos+1;
end;
if last.caseID;
keep caseID Thoscost TNumHos FirCost FirNumHos ConCost ConNumHos;
run;

不会，帮明玥顶

data a;
input caseID $        Entdat yymmdd10. hoscost $;
format Entdat yymmdd10.;
cards;
260754 1950-3-31 62973.59
277270 1950-12-23 136719.83
277270 1951-2-27 95801.55
277270 1952-5-22 54787.56
277270 1952-10-5 163104.40
280785 1951-2-28 83876.28
280785 1952-6-23 157131.43
run;
proc sort data=a;
by caseID Entdat;
run;

data out;
set a;
by caseID;
retain firstdate Thoscost TNumHos FirCost FirNumHos ConCost ConNumHos;
if first.caseID then firstdate=Entdat;
if Entdat-firstdate<365 then tag=1;else tag=2;
if first.caseID then do;
Thoscost=0;
TNumHos=0;
FirCost=0;
FirNumHos=0;
ConCost=0;
ConNumHos=0;
end;
Thoscost+hoscost;
TNumHos+1;
if tag=1 then do;
FirCost+hoscost;
FirNumHos+1;
end;
if tag=2 then do;
ConCost+hoscost;
ConNumHos+1;
end;
if last.caseID;
keep caseID Thoscost TNumHos FirCost FirNumHos ConCost ConNumHos;
run;

楼上不错，比较好的办法。