CRFNAME2=substr(CRFNAME,1,4);
结果包括 “0筛”这类数据，

但是，下面要限定这个CRFNAME2条件的时候，0筛 未识别，代码如下：

data a;
set lb;
if CRFNAME2 not in ("0筛","1.03","2.03","1.09","2.09","1.16","2.16","1.17","2.17") then delete;
run;

proc freq data=a;
table CRFNAME2;
run;


是我代码有什么问题吗？0筛 类的数据没能纳入？