During the first half of the twentieth century, knowledge of eighteenth- and nineteenth-century literary norms waned, and , there is no institutionalised standard literary form. By the 1940s, the Scottish Education Department's language policy was that Scots had no value: "it is not the language of 'educated' people anywhere, and could not be described as a suitable medium of education or culture". Students reverted to Scots outside the classroom, but the reversion was not complete. What occurred, and has been occurring ever since, is a process of language attrition, whereby successive generations have adopted more and more features from Standard English. This process has accelerated rapidly since widespread access to mass media in English and increased population mobility became available after the Second World War. It has recently taken on the nature of wholesale language shift, sometimes also termed language change, convergence or merger. By the end of the twentieth century, Scots was at an advanced stage of language death over much of Lowland Scotland. Residual features of Scots are often regarded as slang. A 2010 Scottish Government study of "public attitudes towards the Scots language" found that 64% of respondents (around 1,000 individuals in a representative sample of Scotland's adult population) "don't really think of Scots as a language", also finding "the most frequent speakers are least likely to agree that it is not a language (58%) and those never speaking Scots most likely to do so (72%)".