Which PHP 5 Version is most commonly used?

When I'm developing applications that would be used on client web serves of different configurations, oft开发者_StackOverflow中文版en with shared hosting, which PHP 5 version should I assume most web servers have, e.g 5.2.x, 5.3.x, etc?

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Version 5.2 is used by 84.9% of all the websites who use PHP version 5.

Version 5.3.3 is used by 39.7% of all the websites who use PHP version 5.3

You can see more statistical data from the following link:

http://w3techs.com/technologies/details/pl-php/5.3/all

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WordPress.org also collects stats about installs, you can see results here: WP stats

August 2014 it it 78% for 5.2 & 5.3 which are supposed EOL.