A third of email marketers don’t actively optimize their email marketing, and only about half test subject lines.

So says a new report from email marketing provider GetResponse. Out today, “State of Email Marketing By Industry” surveyed 1,831 marketers last summer around the world in a variety of industries and analyzed more than 700 million emails. Optimization includes ways to improve deliverability and response rates, like testing alternative subject lines or offers, or previewing emails in various clients and browsers.

In fact, although targeting is considered a mainstay of modern digital marketing, the report astoundingly found that 42 percent of marketers send everyone on their list the same email. And the report said that only four percent use behavioral and survey data for personalizing emails and targeting. But — thank goodness — 75 percent are using email automation.

While this detailed industry-by-industry report employed a sizable sample mostly in the US and Europe, co-author Magda Ciszewska told me via email that a large number of the respondents “are newbies to online marketing.”

This could account for the surprisingly high number of marketers sending the same email or the very low percentage using behavioral and survey data. On a related topic, she noted that the report’s authors suspect email automation, although popular, is often being used at a basic level.

Ciszewska added that, while the report verifies “email remains one of the top revenue generating channels with the greatest ROI [return-on-investment],” it also shows “there is still room for improvement [when] it comes to advanced marketing techniques like data segmentation, testing, measurement and optimization.”

On the subject of ROI, an average of 21 percent of marketers across all the surveyed industries say that email marketing provides “an excellent return on investment,” again validating this marketing channel. This tied with SEO for the best ROI. But, as in much else in this report, the actual stats depend on the industry. Affiliate marketers, for instance, report the best ROI with email marketing.

Some other findings:

On average, the top benefit of email marketing for 23 percent of those surveyed is lead generation, followed by improved sales (19 percent) and improved conversion rates (17 percent). Here’s the breakdown for marketers at affiliate networks:

Only about a quarter of the respondents try out alternate offers, but only 18 percent try different layouts and creative.

Not many marketers — only eight percent — in the vacation/hotel/leisure category are using advanced segmentation, such as separately targeting frequent versus occasional travelers or those who take luxury voyages versus those on economy trips.

In the health and wellness sector, only about nine percent employ responsive design so that marketing messages automatically adapt to screen sizes.

But marketers in education are definitely on board with email, with nearly 70 percent reporting “good or excellent” returns on their email marketing investments.

Fifty-seven percent of marketers intend to increase their email marketing budgets this year, while 28 percent will stay put.

The report also includes some suggested best practices, like “let the email team own the list growth process,” optimize how often you send, or test your subject lines to increase opens.

The respondents were obtained from GetResponse’s 350,000+ customers and from 125,000+ members of marketing resources firm Smart Insights. Almost 70 percent were senior managers or executives, while slightly more than a third owned businesses.

Smart Insights offers learning resources “to help businesses improve their marketing results” via a blog, marketing templates, guides, video courses, a weekly newsletter and other resources. GetResponse is based in Gdańsk, Poland, with offices in the US, Canada, and Russia.