countries in the PlSA data. It is reasonable to four NANZ countries together (O.82 points). In ask if the large drops in the NANZ countries, which are all mainly English-speaking, might be due, at least partially, to social media platforms being used differently in other cultures, with countries, there are very large differences in the extent of youth declines in wellbeing, so countries into three groups of two, separated by drops in North America. However, there is likely geography but mainly sharing a common language. the effects of social media. For example, in Australia and New Zealand, with both drops being larger than in the UK and Ireland. The drop than the rest of Canada, which is mainly Western Europe, but not significantly so. The Error bars show 95% confidence intervals. The purple line shows the aggregate decline for all NANZ countries (United States, Canada, Australia, New Zealand; Gallup region 7). Western Europe follows the Gallup region definition (region O), excluding the United Kingdom and Ireland to avoid overlap. The NANZ vs Western Europe differential is tested using a two-sided z-test (p < 0.001). N (baseline / recent): Canada + United States 1,212 / 1,036; Australia + New Zealand 1,341 / 932; United Kingdom + Ireland 1,387 / 800; Western Europe (excl UK + Ireland) 8,982 / 8,007.