That's my curious, If domain was registered or extended for a longer years, Can this help in site ranking or site authoritative?
It might be a small factor The rationale behind it lies in the fact that it gives Google the impression that you are not going to run away soon, and are here to stay and work your way to the top.
Thanks for your clarification. I am thinking if this is a big factor or not. Some of my domains are going to expired and I am thinking about extension for another one year or another 3 years. I may register just another one due to not a big ranking factor.
well i think its a big factor. i have register my major domain till 2017 and i have strong positions in some good keywords
Some some SEO experts think it's a small factor. Also, some experts think that Google downranks sites whose registrations are scheduled to expire in less than one year. So it might be a good idea to always keep the expiration beyond one year.
Google is a top-level registrar for one reason or another... if its not for feeding data into the calculation of the SERPs, I would be surprised.
It's been speculated before that this MAY contribute slightly, though I've never seen any hard evidence. Like mentioned, if it does have an effect, it's very small.