The DMA Email Marketing Council's email benchmarking survey suggests a key factor in this growth is that email is being seen as increasingly cheap and effective, with latest figures also showing a rise in acquisition clickthrough rates, from 6% to 8%.
Another factor, according to council chairman Richard Gibson, is that marketers are getting better at using email as a marketing tool and in targeting prospects.
He said: "The considerable rise in acquisition response rates demonstrates increasing sophistication among clients in terms of their targeting and messaging.
"The report shows that marketers are continuing to invest in email as a channel and are also taking steps to improve via their provider list hygiene."
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