Starting with 12MM[1] in 2004, what you are effectively suggesting is that 1 in 15 Bangladeshis has left India in the last decade[2]. Come on: outside of Superpower 2030 memes, the grass isn't that green in India, and I'd like to think that the first million or Bangaldeshis crossing over would have sent home word that migration wasn't actually worth it. Why go to India and be poor in Calcutta when you can go to the Middle East and make (even factoring in broker fees) 2-3 orders more money for your family?

I'm willing to acknowledge that there have been some cross border shenanigans in the last fifty years, but the statistics trotted out by the Centre are transparently politically motivated, i.e. lies. What is more, these are stupid lies, relying on completely irrational behavior of potential migrants, who in my experience are some of the savviest agents in existence.

[1] 10 million of whom came over in 1971, making for an annual migration of ~50K between 1971 and 2004.

[2] By this measure, every family in Bangladesh would have someone who has left for India in the last decade. This is...not true?