Muslim Brothers & sisters How do you determine "Global Muslim Population"?

A comprehensive 2009 demographic study of 232 countries and territories reported that 23% of the global population, or 1.57 billion people, are Muslims. Of those, an estimated 80–90% are Sunni and 10–20% are Shi'a, with a small minority belonging to other sects. Approximately 50 countries are Muslim-majority, and Arabs account for around 20% of all Muslims worldwide. Between 1900 and 1970 the global Muslim community grew from 200 million to 551 million; between 1970 and 2009 Muslim population increased more than three times to 1.57 billion.

The majority of Muslims live in Asia and Africa. Approximately 62% of the world's Muslims live in Asia, with over 683 million adherents in Indonesia, Pakistan, India, and Bangladesh. In the Middle East, non-Arab countries such as Turkey and Iran are the largest Muslim-majority countries; in Africa, Egypt and Nigeria have the most populous Muslim communities.

Most estimates indicate that the People's Republic of China has approximately 20 to 30 million Muslims (1.5% to 2% of the population). However, data provided by the San Diego State University's International Population Center to U.S. News & World Report suggests that China has 65.3 million Muslims. Islam is the second largest religion after Christianity in many European countries, and is slowly catching up to that status in the Americas, with between 2,454,000, according to Pew Forum, and approximately 7 million Muslims, according to the Council on American-Islamic Relations (CAIR), in the United States.

A true Muslim says that we are all Muslims but we differ in some respects. Those that say Sunni, Shia, Wahabi, Sufi and so on see what separates us and not what unites us, so who is the Muslim?

Is it the one who states the first sentence, while the second sentence only sees the opposite?

To me we are between 1.5 to 2 billion Muslim's and to those that say Islam is declining both in Africa and within the West need to see the real results, where the fact is that when we are attacked it actually gains us more reverts. Only those who live in the land of lies perpetuate those lies, for they do not have the guts to read the truth themselves as most reverts do.