WARNING: The range of variable rirf is so small relative to its mean that there may be loss of accuracy in the
         computations. You may need to rescale the variable to have a larger value of RANGE/abs(MEAN), for example, by
         using PROC STANDARD M=0;
NOTE: 上述消息是针对以下 BY 组的:
      PERMNO=26753
这样的情况该怎么办？而且这样子的意思是只有这一只股票有这样的问题嘛
谢谢