I read this on Dries Buytaert’s blog (he is the guy that created open source content management system drupal). Through a presentation from Nicole Sullivan, a former member of Yahoo’s Exceptional Performance Team and co-author of O’Reilly’s upcoming book on performance optimization, I came across the following data points:
- Amazon: 100 ms of extra load time caused a 1% drop in sales. (Source:Greg Linden, Amazon)
- Google: 500 ms of extra load time caused 20% fewer searches. (Source:Marrissa Mayer, Google)
- Google: trimming page size by 30% resulted in 30% more map requests. (Source: Marrissa Mayer, Google)
- Yahoo!: 400 ms of extra load time caused a 5 to 9% increase in the number of people that clicked “back” before the page even loaded. (Source: Nicole Sullivan, Yahoo!)
Here is the presentation: