Many companies have complaint rates of less than one complaint for every four million dollars in written companies, no small achievement. (netquote.com)
• Maintained a low average complaint rate and consistently received positive evaluations from managers. (resumemycareer.com)
A more complicated implementation may be to whitelist IP addresses with Sender Scores above some threshold but blacklist senders who have recently hit a spamtrap, or who have generated very high complaint rates. (senderscore.org)