Those findings, released today, are part of the DMA's State of the E-commerce Industry Report 2001-2002, which was done in conjunction with the Association of Interactive Marketing.
The two groups surveyed 700 companies involved in direct and interactive marketing.
E-mail marketing promotions led to an increase in sales for 66% of respondents, and 63% said e-mail was the most effective customer-retention tool. E-mail is less effective for customer acquisition, however, with only 37% of respondents indicating its usefulness in attracting new consumers.
Respondents also identified e-mail as a cost-efficient medium: investing only 13% of their total marketing budgets in e-mail generated 15% of total net interactive sales.