Here is a nice code to improve google speed with Leverage Browser Caching for Website:
Include the code in website root .htaccess file
Greg Corrado a senior research scientist interested in biological neuroscience, artificial intelligence, and scalable machine learning for Google has revealed in a Bloomberg interview (http://www.bloomberg.com/news/articles/2015-10-26/google-turning-its-lucrative-web-search-over-to-ai-machines) a significant new algorithm update deployed on 26/10/2015 named RankBrain. In this article, I will attempt to explain what RankBrain is and the impact it might have on ranking.
Google implemented an update to their Mobile-Friendly ranking algorithm on Monday 2nd November 2015 ("An Update To The Mobile-Friendly Algorithm" by Google Webmasters. Google+. November 2, 2015. https://plus.google.com/+GoogleWebmasters/posts/7qKTxCp2PZx). The update focuses on judging how friendly websites are on mobiles and subsequently drop down or penalise any sites deemed to be be non-mobile friendly in searches performed from mobile devices.
This algorithm change will penalize web pages which, when loading, display a large interstitial advertisement to download an app, hiding a significant section of the page content. Google had already stated that he use of such ads was simply not to mobile-friendly, and that their future update would reflect this. Non-compliant pages and websites are now suffering the impact and consequences of this recent change.
Google recommend that "webmasters use more user-friendly formats such as app install banners". By doing so, they continue by writing "we hope that this change will make it easier for searchers to see the content of the pages they are looking for".
We have seen an impact on some of our sites which do not use Interstitial Ads. This suggest that the algorithm is not just about covering the content but also how mobile-friendly your pages are.
We have learned that Google is rolling out a series of new search algorithms which target websites that have been victim of hacking or spam. and could result in fewer search results being shown for certain queries due to hacked results no longer being shown.