What is the data source for you published statistics?

I have had discussions with a number of my colleagues about the numbers of South Asians who work at our company and told them that H1 Visas are limited and restricted. he demographics have defiantly changed in the last 20 years but it is not a conspiracy and it’s not due to people with H1 visas. Many of them call it the “Indian Mafia” and believe the changes were planned. In my opinion we have opening where most applicants are South Asian and native American don’t appear to be interested in working at our company. (Or they don’t have the best qualifications). I would love to prove the facts once and for all and I was wondering where you get the raw data. I would point them to this site but I’m sure they would say “It run by people from India and is probably inaccurate. Is there any way I can get the details from a US government source and if so can you tell me what I need to do? I have been in the US since I was 18 and am Americanized. I don’t say “today morning” and my wife is an ABCD. Any help would be appreciated