以下是对EXCEL文件的注意事项：

1. As much as possible, the values of a variable must be of the same type. SAS uses the first 8 observations to determine the TYPE to assign to the imported column(s). In case of mixed-types, the type that is the most dominant in the first 8 observations will be applied. In case of a tie i.e., four (4) character and four (4) numeric variables, the numeric type takes precedence. Once imported, values that do not conform to the assigned type will be converted to missing values.
2. Make sure that rows immediately following the last observation and columns immediately following the last variable are not activated by deleting them so that SAS will not mistake them for additional observations or additional columns, respectively.

所以，有可能你的EXCEL文件违反了第二条。

希望能够解决你的问题！

可能是你excel之前的记录是300条，后来把后面的两边条“回车”了！

纯属个人意见，仅供参考！