{"footnote":"\u003Cp\u003E  In 1999, Google\u0026rsquo;s web index \u0026ndash; its copy of every page on the internet \u0026ndash; was updated once every three or four months. By 2003 parts of the index were updated once a day, and by 2007 the rate was once  every few minutes. By 2009 it was no longer possible to say that the web was being crawled at such and such a speed: if Google considered there was a chance a page might be updated it engineered  things such that any change on that page was reflected in its index exactly as it happened. A search for \u0026lsquo;hudson river\u0026rsquo; on 15 January 2009 would have showed that a plane had crash-landed on it  before it was reported by CNN.\u003C\/p\u003E\n","audio":[],"video":[]}