Can anyone point me to low bias, nonpartisan analyses about the US immigrant population by practically meaningful cohorts? These sites that rehash aggregate num

Can anyone point me to low bias, nonpartisan analyses about the US immigrant population by practically meaningful cohorts? These sites that rehash aggregate numbers are the most widespread, and the subtext on sites like this is that they provide insightful portrait into who immigrants are -- but this is an incomplete picture that speaks nothing of their admission category and conditions, their fates in the States, their position on socioeconomic metrics by year since their entry. A while back, I was looking for data to quantify the distinction of "Ellis Island"-style open application immigration, vs. the precondition-gated system we have today. I was also trying to understand the socioeconomic differences between employment/skill-based immigrants (of various admission categories) and family-based immigrants. But official government sources are spread across multiple agencies, and the cohorts are set in a way that isn't helpful in disaggregating superficially similar people with very different outcomes. In my observations, pro-immigration groups tend to publish data that is difficult to disaggregate (example: this data sheet on 'Profile of the Unauthorized Population: California' [1] by the Migration Policy Institute), while groups that want to restrict immigration (Center for Immigration Studies, The Heritage Foundation) have better cohorts with more practical relevance, but the less flattering data is used by them to justify their various restrictive policies, and their bias raises concerns about their veracity. It's a challenge to find a source that hits the middle ground. [1] https://www.migrationpolicy.org/data/unauthorized-immigrant-population/state/CA https://www.migrationpolicy.org/data/unauthorized-immigrant-...