there was a question by senator graham earlier about tiktok. mr. chiu, you said you invest $2 billion in safety. my background memo says your revenue is $85 billion. you are investing $5 billion in safety. so what matters, what matters is the relative numbers and the absolute numbers. if there's anyone in this world who understands data, it's you guys. i want to walk through whether or not these voluntary measures of disclosure of content and harm are sufficient. i would argue that we are here because they are not. without better information, how can policymakers know whether the protection you testified about, the new initiatives, the starting programs, the monitoring and the takedowns are actually working. how can we understand meaningfully how big these problems are without measuring and reporting data? mr. zuckerberg, you referenced the national academy of science study that said at the population level there's no proof about harm to mental health. it may not be at the population level, what i'm looking at a room with hundreds of parents of --