Symbolic addresses of top 20 spammers:
NOTOTSPAM%IP_ADDRESSSYMBOLIC_ADDRESS
11100.0212.76.76.242PTR_INVALID
11100.0213.92.10.225relay.ntvspa.it
11100.05.178.121.11m11-a.static.sndthreezero.com
11100.05.39.90.103iomail.info
11100.054.240.10.27a10-27.smtp-out.amazonses.com
11100.054.240.11.124a11-124.smtp-out.amazonses.com
11100.054.240.11.4a11-4.smtp-out.amazonses.com
11100.05.9.80.113news01.nierle.com
11100.062.4.0.8510.fqtww.com
11100.076.164.216.16476-164-216.unassigned.userdns.com
11100.091.197.72.193mailzgbaic.mail.dmdelivery.com
11100.093.90.122.31relay290.mysmtp.mobi
1250.013.111.20.3mta.email.flixbus.com
22100.0157.7.166.57ce.ptr34.ptrcloud.net
22100.0167.89.110.105o28.em.wageningenacademic.com
22100.0198.11.176.86PTR_INVALID
22100.051.254.66.155a155.my.topselection-vip.com
22100.05.178.121.1m1-a.static.sndfourzero.com
22100.05.249.146.72server.infoebit.it