The fourth wave was carried out across 7 countries in 2016. The fifth wave (2018-19) was carried out across 12 countries and included larger sample sizes (2,400 respondents) in most countries. In total, more than 25,000 surveys were carried out making this the largest and most in depth publicly available survey ever carried out across the Middle East and North Africa.[8] The survey was conducted in partnership with the BBC Arabic.