In 2006, 2007, and 2008, <a href="https://en.wikipedia.org/wiki/Gallup_poll" class="extiw" title="en:Gallup poll">Gallup</a> asked representative samples in 143 countries and territories whether religion was an important part of their daily lives. This map is based on the results, and shows religiosity by country, ranging from the least religious to the most religious on a relative basis.
<a href="//commons.wikimedia.org/wiki/User:Sbw01f" class="mw-redirect" title="User:Sbw01f">Sbw01f</a>
CC BY 3.0
Self made, data from <a rel="nofollow" class="external text" href="http://www.gallup.com/poll/114211/Alabamians-Iranians-Common.aspx">2009 Gallup poll</a>.