Although 311,127 Australians were affected by the Cambridge Analytica data leak, only 53 of the country's citizens accepted the Facebook questionnaire responsible for obtaining and misusing personal information, according to The Guardian. Similarly, 63,724 people in New Zealand were affected, but only 10 New Zealanders downloaded the questionnaire.
It is reasonable to assume that many of the people in Australia and New Zealand were impacted by a friend in their own country, but that is probably very different from everyone's accounting. These numbers also demonstrate the dominant effects of the friends of overseas users who granted permissions to the personality questionnaire application, called "thisisyourdigitallife".
It is possible that up to 87 million Facebook users have had their information compromised, including more than 1 million people in the United Kingdom, the Philippines and Indonesia. Facebook now shows a link at the top of the News Feed, which aims at people removing applications they no longer need. Users can also visit a page in the Facebook help center that will inform you if you or a friend were affected and what information was potentially shared.
Facebook is implementing changes to the platform to prevent something similar from happening in the future, even looking for "suspicious activity" from the developers to audit them, after making similar changes in 2014. Today, Facebook CEO Mark Zuckerberg is testifying before Congress to answer questions about the use of your company and the protection of user data.