In the 1980s, the “Band Aid” and “Live Aid” campaigns caused quiet mirth for using the slogan ‘Do They Know It’s Christmas?’ to raise money for the poor in sub-Saharan Africa – a region in which, of course, a significant proportion of the population is non-Christian. Nonetheless, the jingle’s inventors at least had time on their side. Over the course of history, the proportion of people celebrating Christmas has been rising steadily, and now covers almost a third of humanity – including a growing number of Africans.
