India recorded 57,264 Parsis at the 2011 census. In 1921 the figure was 101,778. The community has lost more than two-fifths of its number in ninety years, through emigration and a birth rate well below replacement, and this is the central fact of contemporary Parsi life rather than a background trend.
Global Zoroastrian figures are commonly given as 110,000 to 120,000, with perhaps 15,000 to 25,000 in Iran and around 22,000 in North America. Published estimates range far more widely than that, because they disagree about whether to count self-identification and converts, so the range reflects the conversion dispute rather than uncertainty about arithmetic.
Parsi prominence in modern India is genuinely disproportionate. In industry, law, the armed forces, music and philanthropy, a community of tens of thousands has supplied names known to hundreds of millions. That prominence is sometimes cited within the community as a reason the decline is bearable, and by others as evidence that it is not.
The demographic argument and the conversion argument are the same argument. A community that does not accept converts, does not count the children of women who marry out, and has a fertility rate around one, has a determinate future. Some Parsis regard opening the boundary as the only way to survive; others regard the boundary as the thing being preserved, and hold that a community admitting anyone has not survived but been replaced. Neither side disputes the numbers.
Funerary practice has had to change as well: exposure of the dead in the towers depends on vulture populations, which collapsed across South Asia from the 1990s.