“The growth of Islam in Indonesia based on statistical data in 2000 and 2010 decreased one per cent. In the same period, Christianity grew rapidly. Nevertheless, nationally Islam remains a majority with the number of adherents of 207.2 million or 87.18 percent.”
The data was revealed in a book entitled Agama di Indonesia dalam Angka: Dinamika Demografis Berdasarkan Sensus Penduduk Tahun 2000 dan 2010 (Religion in Indonesia by the Numbers: Demographic Dynamics Based on Population Census of 2000 and 2010) written by Agus Indiyanto of the Center for Religious and Cross-cultural Studies at Gadjah Mada University (UGM CRCS).
On the other hand, in some provinces the growth of the Muslim population rose. Agus predicted that it is due to migration.
The growth of 4.85 percent reached in Bali, East Kalimantan 3.86 percent, and Bangka Belitung 3.37 percent. Meanwhile, Christian growth nationally, said Agus, is the highest in the period 2000 and 2010.
There are six studied religions, namely Islam, Christianity, Catholicism, Hinduism, Buddhism, and Confucianism. According to Agus, Christians nationwide totaled 16.5 million or 9.96 percent. Meanwhile, Catholics embraced by 6.9 million people, or 2.91 percent.
Buddhism is almost stagnant or not growing at all. Its growth is only 9000 people in the last 10 years. Agus claimed has no information on the cause of the stagnant growth of Buddhism yet.