How many NY/NJ residents have moved to Southern Calif?

Question

As part of a wider research project, I am trying to find out how many residents from the "east coast" (NY/NJ/Ohio) currently live in the SoCal area - greater Los Angeles and maybe Orange County and San Diego. The US Census data has some numbers on how many residents lived in a different state in the US 5 years ago and 1 year ago, but there is no further breakdown about which state these ppl may have lived earlier. Is there any source of data (census or otherwise) that is available for free and can help answer this question?

Answer 1

An exact number is probably unknowable.

However, you could use the census data for those states you mentioned to determined overall departures and then create an extrapolation algorithm to approximate the result you seek.

Answer 2

2.2 million moved because of weather conditions and surplus of work.