Here are some of the most interesting digital marketing stats we’ve seen this week.

Stats include email marketing ROI, Twitter hashtags, user experience testing, global adspend, The Rolling Stones and Google Shopping.

For more digital marketing stats, check out our Internet Statistics Compendium.

66% of marketers say email delivers ‘excellent’ or ‘good’ ROI

  • But in spite of the strong potential for delivering a great return in investment, companies are spending too little time on optimisation of campaigns compared to design and content.
  • Only 39% of in-house marketers rate the performance of their company’s campaigns as ‘excellent’ or ‘good’, while 15% admit their campaigns are ‘poor’.
  • More than a quarter (27%) state that they spend no time at all internally on optimising their email campaigns, a figure that has increased from 21% in 2008.

Mobile adspend boom in Germany

  • Increased usage of smartphones and tablet means that mobile adspend is likely to grow by 70% in Germany this year, according to BVDW.
  • Advertisers spent €62m in 2012, but this figure is predicted to grow to €105m this year.
  • The automotive sector was the heaviest investor in the mobile channel, spending €11.7m over the year, which amounted to 18.9% of the total.

20% of consumers think hashtags are mainly useful for researching products

  • One in five (20%) consumers believe that hashtags are primarily useful for finding information on brands and products, though the most common use is for identifying trends (30%).
  • The findings come from a RadiumOne survey into consumer attitudes towards hashtags, which also revealed that out of the 58% of respondents that said they use hashtags, more than two thirds (70%) said they use them on a mobile device.
  • Half of those surveyed (50%) stated that they would share hashtags more often than they do now in return for discounts and 17% said they would be willing to post the promotion on their social profiles or follow the brand associated with the content if they weren’t already.

11% of businesses spend more than £100k on UX testing per year

  • Almost half of businesses (47%) that carry out user experience testing spend less than £10,000 per year on such initiatives, while 7% don’t actually spend anything at all.
  • In contrast, 11% of businesses spend more than £100,000 each year on UX testing.
  • The findings come from the Econsultancy and WhatUsersDo User Experience Survey Report, which is based on a survey of more than 1,400 professionals working for brands, agencies and specialist user experience firms.
  • The report shows that almost half of companies (49%) that run UX testing are planning to increase their budget in the next 12 months, with just 8% planning to spend less on UX testing over the next year.

Online accounts for 20% of global adspend

  • Online accounted for 19.5% of global advertising expenditure in  2012 and is predicted to  rise to more than 21% this year, according to a report from GroupM.
  • Digital advertising spend reached $99bn worldwide in 2012, a 16.2% increase year-on-year. This figure is predicted to grow by 14.6% to $113.5bn in 2013.
  • North America was the leading digital ad market in 2012, worth $38.3bn, followed by Asia Pacific on $30.6bn and Western Europe on $24.1bn.
  • Ecommerce generated an estimated 40% of online paid media ad investment.

Rolling Stones teaser campaign reaches 28m Twitter users

  • Data from 1000heads shows that The Rolling Stones teaser campaign for their summer tour potentially reached 28.6m Twitter users.
  • The results show that in the six-days leading up to the big reveal the hashtag #StartMeUpWednesday was used 9,000 times by almost 5,000 unique users, with around two-thirds of these mentions (65%) taking place during the immediate build up to the announcement.
  • When the tour was finally revealed there were more than 1,800 uses of the hashtag in a single hour, which would account for fewer than 1% of the band’s 332,434 Twitter followers.

  • 74% of these tweets were retweets of existing content, primarily relaying details about the tour and information concerning the timings of the announcement itself.

APAC internet adspend to hit $60bn by 2017

  • A new Forrester report predicts that internet adspend in Asia Pacific is set to record a compound annual growth rate of 23% over the period to 2017, when it should stand at $60bn overall.
  • The report predicts that China wil account for 58% of the region’s online advertising market by the end of this period.

56% of smartphone owners also own a tablet

  • A YuMe survey of 1,340 people that own at least one internet-connected device has highlighted the fact that majority of these people own multiple ‘smart’ devices.
  • Overall, some 96% of respondents to the survey used a smartphone, while 72% possessed a laptop and 60% had already purchased a tablet.
  • A 56% majority of smartphone users also owned a tablet, while 44% of the panel had access to all three of the devices assessed.
  • The recall of pre-roll video commercials stood at 40%, compared with only 16% for banners, totals that proved largely consistent across each medium.

Google Shopping integrations in universal search drop 79% after shift to paid model

  • Google’s decision to move its Shopping product from a free to a paid-for service has coincided with a massive decline in the number of shopping results showing up in universal search integrations on
  • A new report from Searchmetrics shows that in January 2012 shopping results appeared in 20% of universal search integrations, however by December this number had fallen to just 5%.

  • The steepest decline occurred in October, which is also the month that Google made the switch to a paid-for model.
  • Overall the data shows that the proportion of keywords with at least one universal search integration declined throughout 2012. In January the proportion was about 86% but by December it had decreased to 75%.
  • In the same period the integration of images remained constant at around 30%, but for video it declined from 76% to 62%.

Argos tops search chart for cooking appliances

  • UK web search volumes for cooking appliances in February increased 5% on the previous quarter and at the expense of refrigeration, dishwasher and laundry products, according to Greenlight.
  • Cooking appliances were the only white good subsector to see an increase in the volume of search traffic, which increased from 253,232 in November to 265,988 in February making up a 34% share of all white goods-related search queries, up from 30% the previous quarter.
  • Greenlight’s report also ranked the most visible sites for cooking appliances in natural search based on how visible they were for the most popular keyword searches.
  • Argos topped the table attaining a 36% share of voice in natural search. It was visible to 88,341 cooking appliance-related searches.
  • Amazon UK, which the previous quarter ranked second behind Argos, was relegated to fourth position as Appliances Online moved up three places to take second spot whilst Tesco moved up a notch to rank third.