![[LISTSERV - the mailing list management classic]](https://www.lsoft.com/images/HDR-LISTSERV-sm.gif)
There are many possible ways to measure the relative "importance" or "size" of LISTSERV sites: number of lists, number of subscribers, number of messages delivered, etc. In most cases, the number of messages delivered is used to rank mailing list managers, because it is the most accurate measurement of the amount of activity on the server. But, depending on what you are looking for, other variables may be more appropriate. There are currently three LISTSERV "Top 20" lists, ranking the various servers according to:
In addition, you can view a list of the Top 20 lists in the network (by number of subscribers).
The statistics are gathered daily by a monitor at L-Soft which polls all the LISTSERV sites that participate in the "open" LISTSERV network over the worldwide Internet. Corporate servers operating in a "closed" environment are not included.
The statistics are organized in monthly reports. The message volume figures are a flat average of the accumulated traffic for the entire month. Thus, a server that delivers 300,000 messages per month will show a daily average of 10,000 messages. In practice, there is a lot less traffic during the weekend, and even during business days there can be significant fluctuations (~30%). The list statistics (number of lists, number of subscribers, largest lists in the network) are measured as of the last day in the month.
For the current month, the message volume figures are averaged based on the number of days that have elapsed. In practice, the figures are not very meaningful in the first few days, especially if the month starts on a weekend. In that case it is best to refer to the previous month for more accurate figures.
A fourth "Top 20" list is available for the more technically oriented: Number of messages generated by the server. This corresponds to the number of mail messages created by the server while processing postings to its mailing lists. LISTSERV delivers its mail using an intelligent mail delivery function called DISTRIBUTE, which improves mail delivery times and reduces bandwidth usage by spreading the delivery chore over scores of participating servers. Each of these servers processes the recipients for its service area (typically its organization or campus). In most cases, DISTRIBUTE simply alters the manner in which the mail is delivered, and the number of messages forwarded to other sites for optimized delivery is roughly equal to the number of messages received by other sites for the same purpose. In some cases, however, this is not the case, either because the server elected to serve a much wider service area than its own organization, or because it is explicitly forwarding all its deliveries to another machine (for instance, many mainframe-based servers forward their mail to a workstation or PC for delivery).
Pos Recipients Site --- ---------- ---- 1 1061837 LIST.ETSI.ORG (Windows Server 2016 Datacenter x64 Edition) 2 566748 JISCMAIL.AC.UK (Windows Server 2019 Standard x64 Edition) 3 328577 LISTS.PSU.EDU (Linux 3.10.0) 4 310679 LISTS.HAWAII.EDU (Linux 3.10.0-1160.36.2.el7.x86_64) 5 254704 DISCUSSIONS.EQ.EDU.AU (Linux 3.10.0-1160.31.1.el7.x86_64) 6 205968 LISTSERV.TAMU.EDU (Linux 3.0.101) 7 196808 LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition) 8 186318 LISTSERV.LIV.AC.UK (Linux 3.10.0) 9 169450 LISTSERV.ACM.ORG (Windows Server 2012 R2 Datacenter x64 Edition) 10 152930 LISTSERV.NODAK.EDU (Windows Server 2019 Standard x64 Edition) 11 141984 LISTSERV.UIC.EDU (Linux 2.6.32-504.8.1.el6.x86_64) 12 134498 LISTS.UFL.EDU (Linux 2.6.32) 13 133644 LSV.UKY.EDU (Windows Server 2019 Datacenter x64 Edition) 14 131776 LISTSERV.SYR.EDU (Windows Server 2019 Standard x64 Edition) 15 119448 LISTES.ULAVAL.CA (Linux 3.10.0) 16 118995 LISTSERV.AAP.ORG (Windows Server 2012 R2 Standard x64 Edition) 17 117444 LIST.UNM.EDU (Linux 3.10.0-1160.36.2.el7.x86_64) 18 112111 LISTSERV.BUFFALO.EDU (Linux 3.10.0) 19 112075 LISTSERV.UCONN.EDU (Windows Server 2019 Datacenter x64 Edition) 20 109956 LISTS.ROCHESTER.EDU (Windows Server 2012 R2 Standard x64 Edition)
Pos Subscribers Site --- ----------- ---- 1 5583445 LISTES.ULAVAL.CA (Linux 3.10.0) 2 4997284 LISTS.PSU.EDU (Linux 3.10.0) 3 1777535 LISTSERV.TAU.AC.IL (Linux 2.6.9) 4 1604420 LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition) 5 1258849 LISTSERV.TAMU.EDU (Linux 3.0.101) 6 1193317 LISTSERV.UTORONTO.CA (Linux 3.10.0) 7 1059036 LISTS.UFL.EDU (Linux 2.6.32) 8 1041058 LISTS.WAYNE.EDU (Linux 2.6.32) 9 1037895 LSV.UKY.EDU (Windows Server 2019 Datacenter x64 Edition) 10 1022501 LISTSERV.UA.EDU (Linux 4.12.14) 11 938217 LISTS.UMN.EDU (Linux 3.10.0) 12 867896 LISTSERV.BUFFALO.EDU (Linux 3.10.0) 13 853488 LISTSERV.UTA.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 14 825501 LISTSERV.UH.EDU (Linux 3.10.0) 15 808734 LISTSERV.SYR.EDU (Windows Server 2019 Standard x64 Edition) 16 808281 LISTSERV.ECU.EDU (Windows Server 2016 Standard x64 Edition) 17 781581 LIST.MSU.EDU (Linux 3.10.0) 18 754135 LISTSERV.MIAMIOH.EDU (Windows Server 2016 Standard x64 Edition) 19 691632 LISTSERV.LIV.AC.UK (Linux 3.10.0) 20 672582 LISTSERV.UC.EDU (Windows Server 2019 Datacenter x64 Edition)
Pos Lists Site --- ----- ---- 1 34561 LISTES.ULAVAL.CA (Linux 3.10.0) 2 16410 LISTS.PSU.EDU (Linux 3.10.0) 3 14174 LISTSERV.TAU.AC.IL (Linux 2.6.9) 4 9788 LISTS.CLEMSON.EDU (Linux 2.6.18) 5 9599 LISTS.UFL.EDU (Linux 2.6.32) 6 8079 LISTSERV.TECHNION.AC.IL (Linux 2.6.32) 7 7631 LISTSERV.LIV.AC.UK (Linux 3.10.0) 8 6751 LISTSERV.MIAMIOH.EDU (Windows Server 2016 Standard x64 Edition) 9 6000 LISTSERV.UTORONTO.CA (Linux 3.10.0) 10 5048 LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition) 11 4994 LISTSERV.TAMU.EDU (Linux 3.0.101) 12 4835 LISTS.UMN.EDU (Linux 3.10.0) 13 4361 LISTSERV.SYR.EDU (Windows Server 2019 Standard x64 Edition) 14 4193 LSV.UKY.EDU (Windows Server 2019 Datacenter x64 Edition) 15 3819 LISTSERV.BUFFALO.EDU (Linux 3.10.0) 16 3731 LISTS.QUEENSU.CA (Linux 3.10.0) 17 3572 LISTSERV.NODAK.EDU (Windows Server 2019 Standard x64 Edition) 18 3357 LISTSERV.BROWN.EDU (Linux 3.10.0) 19 3355 LIST.UVM.EDU (Linux 2.6.32) 20 2771 LISTSERV.KENT.EDU (Windows Server 2012 R2 Standard x64 Edition)
Pos Recipients Site --- ---------- ---- 1 1060013 LIST.ETSI.ORG (Windows Server 2016 Datacenter x64 Edition) 2 541009 JISCMAIL.AC.UK (Windows Server 2019 Standard x64 Edition) 3 325490 LISTS.PSU.EDU (Linux 3.10.0) 4 309698 LISTS.HAWAII.EDU (Linux 3.10.0-1160.36.2.el7.x86_64) 5 254460 DISCUSSIONS.EQ.EDU.AU (Linux 3.10.0-1160.31.1.el7.x86_64) 6 202476 LISTSERV.TAMU.EDU (Linux 3.0.101) 7 192639 LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition) 8 180847 LISTSERV.LIV.AC.UK (Linux 3.10.0) 9 149794 LISTSERV.NODAK.EDU (Windows Server 2019 Standard x64 Edition) 10 141775 LISTSERV.UIC.EDU (Linux 2.6.32-504.8.1.el6.x86_64) 11 133131 LISTS.UFL.EDU (Linux 2.6.32) 12 131627 LSV.UKY.EDU (Windows Server 2019 Datacenter x64 Edition) 13 119237 LISTES.ULAVAL.CA (Linux 3.10.0) 14 118636 LISTSERV.AAP.ORG (Windows Server 2012 R2 Standard x64 Edition) 15 117253 LIST.UNM.EDU (Linux 3.10.0-1160.36.2.el7.x86_64) 16 111829 LISTSERV.UCONN.EDU (Windows Server 2019 Datacenter x64 Edition) 17 108149 LISTSERV.BUFFALO.EDU (Linux 3.10.0) 18 93823 LISTSERV.UA.EDU (Linux 4.12.14) 19 89595 LISTSERV.SYR.EDU (Windows Server 2019 Standard x64 Edition) 20 88734 LISTSERV.UTRGV.EDU (Windows Server 2016 Standard x64 Edition)
Pos Subscribers Site --- ----------- ---- 1 59200 CAREERCENTERUPDATE@LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition) 2 54050 AMIS-CNRS-INTERNATIONAL-L@IN2P3.FR (Linux 3.10.0) 3 41813 OPSWNEWS@LISTSERV.NYSED.GOV (Linux 4.12.14) 4 41567 SAFETYNOTICE@LISTSERV.UC.EDU (Windows Server 2019 Datacenter x64 Edition) 5 34587 TCUATHLETICSDIRECTOR@LISTSERV.TCU.EDU (Windows Server 2012 R2 Standard x64 Edition) 6 33988 CMU-BASKETBALL@LS2.CMICH.EDU (Linux 3.10.0) 7 31621 TAU-STU-ACADEMICSEC-STUDENTS@LISTSERV.TAU.AC.IL (Linux 2.6.9) 8 28887 TAU-INNOVTL-ALL-STUDENTS@LISTSERV.TAU.AC.IL (Linux 2.6.9) 9 28549 HALLCOLIBRARY-L@LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition) 10 28286 L-THON-NEWS@LISTS.PSU.EDU (Linux 3.10.0) 11 27707 RECREATION@LISTSERV.MIAMIOH.EDU (Windows Server 2016 Standard x64 Edition) 12 27479 TAU4U@LISTSERV.TAU.AC.IL (Linux 2.6.9) 13 27382 VOLUPDATE@LISTSERV.UTK.EDU (Linux 3.10.0) 14 27348 UTENNSRP@LISTSERV.UTK.EDU (Linux 3.10.0) 15 26421 PARENTS@LISTSERV.TAMU.EDU (Linux 3.0.101) 16 24992 NCHPAD-NEWS@LISTSERV.UAB.EDU (Linux 3.10.0) 17 24459 ECF-MIWD@NYED.USCOURTS.GOV (Linux 3.10.0) 18 24288 EXCEL@LISTSERV.UTA.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 19 22770 STUDENT-TRAVEL-SURVEY-L@LISTSERV.OKSTATE.EDU (Windows Server 2012 Datacenter x64 Edition) 20 21994 PRESIDENT-WELCOME@LISTSERV.TAU.AC.IL (Linux 2.6.9)