Because it's really annoying the direct marketers...
One in three people change their email address once a year, due to changing ISPs, switching jobs or just trying to out-run the spammers.
However, this practice is making life hard for marketing firms or others who rely on their database to drive their business.
The Direct Marketing Association (DMA) found that email addresses are changing at a rate of 31 per cent per year. The official findings of the survey, conducted independently by NFO, will be revealed next week at the DMA's 85th annual conference.
Matt Blumberg, CEO of Return Path which offers users the chance to contact people who have changed email addresses, said: "The rate of email address turnover continues unabated. And in addition to the impact on consumer relationships identified, there is a real and significant subsequent financial impact on reputable businesses that rely on email to communicate with their customers."
The survey also revealed that the average person now has three email addresses - often at least one web mail address, one ISP address and a work address.
Forty-three per cent of respondent said changing their ISP was the main reason for switching email addresses. Forty-one per cent said they had changed email addresses because of a change of job and 16 per cent said trying to avoid spam was the reason behind their switch.