It would be impossible to answer this question accurately.
In the first place, groups don't usually keep statistics on whether a convert's former religion was deep and real or just nominal.
In the second place, it is difficult to distinguish between people who have truly converted to a religion and people who simply pretend to change because they want to marry someone or because there are commercial advantages.
In the third place, most Muslim societies make it very difficult for anyone to give up Islam. Many people who do leave Islam for Christianity, Buddhism or just Atheism won't admit to the change out loud.
It is a fact that some Muslims become Christians and some Christians become Muslims, but that is all we can really say.
May be in next 25 years... islam is spreading like anything in western countries (by conversion from Christianity to Islam)
The government allows several specific churches, but conversion from Islam to another religion is prohibited.
Islam, Judaism and Christianity.
The ratio is approximately 23:33. However, it is not clear whether the figures refer to those practising a religion or merely born into it.
Christianity, Islam
Islam, Christianity
The Bible is to Christianity as the Qur'an (Koran) is to Islam.
Judaism, Christianity, and Islam have all claimed the Holy Land for themselves.
Christianity, but Islam may overtake Christianity relatively soon.
Christianity is to Bible as Islam to Quran.
A conversion factor is a ratio equivalent to one.
Judaism, Christianity, and Islam religions.