clear

input str20 Stc str20 Enddt str20 type rev
C000002 2002-03-31 Q1 549639027
C000002 2002-06-30 Q2 952349935
C000002 2002-09-30 Q3 852491194
C000002 2002-12-31 Q4 2.22E+09
C000002 2003-03-31 Q1 779794223
C000002 2003-06-30 Q2 1.411E+09
C000002 2003-09-30 Q3 1.074E+09
C000002 2003-12-31 Q4 3.115E+09
C000002 2004-03-31 Q1 1.031E+09
C000002 2004-06-30 Q2 1.438E+09
C000002 2004-09-30 Q3 1.006E+09
C000002 2004-12-31 Q4 4.192E+09
C000002 2005-03-31 Q1 1.886E+09
C000002 2005-06-30 Q2 2.449E+09
C000002 2005-09-30 Q3 1.222E+09
C000002 2005-12-31 Q4 5.003E+09
C000002 2006-03-31 Q1 2.304E+09
C000002 2006-06-30 Q2 4.366E+09
C000002 2006-09-30 Q3 1.839E+09
C000002 2006-12-31 Q4 9.41E+09
C000001 2002-03-31 Q1 549639027
C000001 2002-06-30 Q2 952349935
C000001 2002-09-30 Q3 852491194
C000001 2002-12-31 Q4 2.22E+09
C000001 2003-03-31 Q1 779794223
C000001 2003-06-30 Q2 1.411E+09
C000001 2003-09-30 Q3 1.074E+09
C000001 2003-12-31 Q4 3.115E+09
C000001 2004-03-31 Q1 1.031E+09
C000001 2004-06-30 Q2 1.438E+09
C000001 2004-09-30 Q3 1.006E+09
C000001 2004-12-31 Q4 4.192E+09
C000001 2005-03-31 Q1 1.886E+09
C000001 2005-06-30 Q2 2.449E+09
C000001 2005-09-30 Q3 1.222E+09
C000001 2005-12-31 Q4 5.003E+09
C000001 2006-03-31 Q1 2.304E+09
C000001 2006-06-30 Q2 4.366E+09
C000001 2006-09-30 Q3 1.839E+09
C000001 2006-12-31 Q4 9.41E+09

end

des
sum

format rev %12.0g

*日期变量调整
generate date=date(Enddt,"YMD")
format   date  %d


gen year = year(date)
gen month=month(date)
gen day  =  day(date)

list year month day  date

sum

*
sort Stc year month

by Stc year: gen quarter=_n
***************************************************
gsort Stc year quarter
gen rev0=rev
format rev0 %12.0g

*第一个问题的
*这就是替换的命令
by Stc year: replace rev=rev-(rev[_n-1]+rev[_n-2]+rev[_n-3])    if quarter==4
list  year quarter rev0 rev

*第二个问题
by Stc year: gen rev1=(rev-rev[_n-1])
list  year quarter rev0 rev rev1

gen      index=1 if rev1 >0 & rev1~=.
replace  index=0 if rev1 <0
list  year quarter rev0 rev rev1 index

谢谢！我试试看。

楼主：善哉！成功，非常感谢,rev0没有用。

我怕把原始的数据更改了
产生个新的操作

版主:太谢谢了！你很有威望！