The audit information is stored by default in the csv files. The audit event csv handler settings allow to change the size of generated files (File Rotation) and the number of files kept in a directory (File Retention). If File Rotation Suffix doesn't generate a unique suffix (timestamp) OpenAM is able to generate, in the worth case, only two audit files of one type. One current file - without the suffix and one historical file - with the non-unique / constant suffix. This is because the previous files are overridden by the new files. The number of actually kept historical files can be significantly less than expected Maximum Number of Historical Files set in the File Retention policy.