A study has shown that paid search advertising has decreasing effectiveness online in the UK. The marketing firm Varn collated data from July this year that shows that over half of those aged 18 to 24 don't recognise a paid ad on a Google results page. Additionally, of those who did, only 8% clicked on them, down from 13% in February. This is despite the data showing that younger users were far more likely to recognise the ads than older users, where for example only 30% of those aged over 65 knew what they were. Despite the evidence however, eMarketer has estimated that search ad spend will make up half of all digital marketing budgets this year in the UK, showing no signs of decreasing. It says that even by 2020, it is still expected to make up the largest share.