This is for a bit of narration in a documentary, so I want to be as
accurate as possible.  There seems to big disagreement on statistics
on Islam.  I've already spent hours online and am stymied.  For each
new bit of data I find, another one contradicts it. Some groups are
accusing other groups of padding the numbers and some of the online
data goes back to 1991 if you read it closely.  The U.S. Census
website has info from 2000, but I was hoping to find some more up to
date stats.  Can it be settled that --
a) Is Islam the "fastest growing" or the "SECOND" fastest growing
religion in the world?
b) Is Islam the "fastest growing" or the "SECOND" fastest growing
relgion in the U.S.
c) What are the most up to date statistics for Global and U.S.?
I've found 1.2 billion, 1.7 billion, 1.6 billion -- worldwide.  
20% of the world population. 1 out of every 5 people in the 5 billion
people in the world.  The U.S. statistics have been difficiult to
track down, too.

I need to be able to state something definitive -- even if the
definitive statement has to be "Somewhere between 1 and 2 billion" or
something like that.

I keep thinking there's some authoritative source that YOU know about
and I don't!  Give me some juicy statistics!

P.S.  I'm not posting the above as separate questions, as I figure
you're likely to find all the answers by finding one answer.  If this
proves to be wrong -- I can make them separate questions if need be.  
  Thanks.



I'm not posting these as separate questions because if you find one,
you'll probably find the others.  The problem is, I've found LOTS of
stats, but have yet to hit anything really current.  There's the US
Census Bureau, but it's 2000 and there are lots of charts dated 1991
and then some groups are claiming other groups are padding the
answers, etc. etc.  I think I'm a pretty good researcher, but am weak
on where to find good statistics

Here are a few statistics I found.  I am not sure if they are the same
ones you did..
In 1990, the Muslim population in US was approx 500,000.  In 2000, the
Muslim population grew to approximately 1.1 million.

There are no official U.S. census statistics since Public Law 94-521
prohibits the U.S. gov't from asking a question on religious
affiliation on a mandatory basis; therefore, the Bureau of the Census
is not the source for information on religion.
According to the 2004-2005 Statistical Abstract of the United States,
the Self Described Religious affiliations of the US population states:
there were approximately 527,000 Muslims in the U.S. in 1990.  In
2001, there were approximately 1,104,000 Muslims living in the U.S.
 

These are the sources in regard to the U.S.
Sources:
http://islam.about.com/library/weekly/aa120298.htm
http://www.islamicweb.com/begin/statistics.htm
http://wikitravel.org/en/United_States_of_America
http://www.adherents.com/rel_USA.html
http://www.adherents.com/rel_USA.html
http://www.census.gov/prod/www/religion.htm
http://www.csmonitor.com/cgi-bin/getasciiarchive?script/2001/11/29/p11s2.txt
http://www.washingtonpost.com/ac2/wp-dyn?pagename=article&contentId=A7459-2001Nov23&notFound=true
------------------------------------------------------------------------------

Exerpt from: http://www.nationmaster.com/encyclopedia/Demographics-of-Islam

"Based on the percentages published in the 2005 CIA World Factbook
("World"), Islam is the second-largest religion in the world.
According to the World Network of Religious Futurists, the U.S. Center
for World Mission, and the controversial Samuel Huntington, Islam is
growing faster numerically than any of the other major world
religions. Ontario Consultants on Religious Tolerance estimate that it
is growing at about 2.9% annually, as opposed to 2.3% per year global
population growth. This is attributed either to the higher birth rates
in many Islamic countries (six out of the top-ten countries in the
world with the highest birth rates have a Muslim majority [1]) and/or
high rates of conversion to Islam.
Commonly cited estimates of the Muslim population today range between
900 million and 1.4 billion people (cf. Adherents.com); estimates of
Islam by country based on US State Department figures yield a total of
1.48 billion, while the Muslim delegation at the United Nations quoted
1.2 billion as the global muslim population in Sept 2005.
Only 18% of Muslims live in the Arab world; 20% are found in
Sub-Saharan Africa, about 30% in the Indian subcontinental region of
Pakistan, India and Bangladesh, and the world's largest single Muslim
community (within the bounds of one nation) is in Indonesia. There are
also significant Muslim populations in China, Europe, Central Asia,
and Russia.
Austria was the first European country to recognise Islam as an
official religion, while France has the highest Muslim population of
any nation in Europe, with up to 6 million Muslims (10% of the
population[2]). Albania is said to have the highest proportion of
Muslims as part of its population in Europe (70%), although this
figure is only an estimate (see Islam in Albania). The number of
Muslims in North America is variously estimated as anywhere from 1.8
to 7 million."

On the link above, you will also see further links which will take you
to the statistics for the populations of Islam in the world.
Go to this link to get the information of the world by year by
religion: http://www.census.gov/ipc/www/idbconf.html

Islam populations statistics of the World Sources:
http://www.nationmaster.com/encyclopedia/Demographics-of-Islam
http://www.census.gov/ipc/www/idbconf.html
http://www.religioustolerance.org/growth_isl_chr.htm


For further analysis, you may want to consider UNESCO Statistical
Yearbook, Statistical Yearbook   (United Nations), International
Historical Statistics, Statistical Abstract of the World.  These books
can be found in your state library.

Hope this helps.

Thank you for taking the time to post this, icecube.  I had hit a lot
of those sites, but not all of them.  It's really tough to boil it
down to a few sentences.  Today I came across a very thorough bunch of
information on BBC News, UK edition.  It quotes US State Dept.
Statistics.  I don't know what year they're quoting, but most of the
BBC report is dated from 2003 -2004, so it's encouraging.  They say
1.2billion people in Muslim countries.  About 6 million American
Muslims.  So the 1.2 billion seems to be almost in synch with the
State Dept. quote you listed and is identical to the UN quote you
listed.

Thanks for your help.  I think I'm going to cancel this question out,
though, since you're not an "official" researcher and none of the
regulars have jumped on the query.  Which means, as I suspected and
you've proved too, the question isn't easy to answer definitively.  
And I need the info now.  Thanks again for your input.  FYI, here's
the BBC link -- a lot of intersting stuff.  All part of their "Islam
and the West" coverage.

http://news.bbc.co.uk/1/shared/spl/hi/middle_east/03/islam_around_the_world/html/default.stm