From Lisa Covi's List Management Tips for Listserv Postmasters & Listowners:
 
Column 81     A= ACK
              a= NOACK
              M= MSGACK
 
Column 82     M= MAIL
              m= NOMAIL
 
Column 83     F= FILES
              f= NOFILES
 
Column 84     blank means NOREPRO
              R= REPRO
 
Column 85     null = SHOTHDR
              F= FULLHDR
              S= FULLBSMTP
              s= SHORTBSMPT
              I= IETFHDR
 
Col. 86-87    yy= subscription or deletion year
Col. 88-90    ddd= julian subscription day or deletion day.
 
Col. 91       null= normal
              D=  deletion pending
              W=  confirmation waived
 
Col. 92       null= NOCONCEAL
              C= ocncealed
 
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                      IRMSS907@SIVM  or  @SIVM.SI.EDU
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