Publication History - Status Legend
| Valid | No material deficiencies known. |
| Upgraded | No material deficiencies but a newer release exists with greater functionality, e.g. more participants. |
| Corrections | Must be used with subsequent correction notices. |
| Caution | There are undocumented data deficiencies. |
| Replaced | This release has been replaced with a newer release, usually to correct data deficiencies. |
| Withdrawn | No longer considered valid but no replacement available. |
| Pending | A correction notice or new release will be available shortly. |