I'll tell you what - tell me what metric is in question, and what percent decrease of it over what period of time would constitute 'collapse', following which I

I'll tell you what - tell me what metric is in question, and what percent decrease of it over what period of time would constitute 'collapse', following which I will read the article and provide my response. Bonus to incentivize: I'll even be providing the weird mix of native-San-Franciscan-cum-tech-person take, being born & raised in the Sunset. Therefore I promise to infuse it with a sense of entitlement & disaffection, as if it was possible to have any scope on in-migration/emigration policy across city limits.