Bilateral migration data is available from sources such as the United Nations Population Division unit on International Migration, Migration Policy Institute, and Migration Data Portal. For example, the 2019 UN dataset for migrant stocks by origin and destination is available as .xlsx here.
From NASA's Socioeconomic Data and Applications Center (SEDAC), I found this dataset: Gridded Population of the World (GPW), v4.
30 arc-second (approx 1 km) native resolution, which is aggregated to four lower resolutions:
2.5 arc-minute (approx 5 km)
15 arc-minute (approx 30 km)
30 arc-minute (approx 55 km)
1 degree (approx 110 km)
ACS data are not aggregated. They are estimates based on 5-years worth of surveys. So essentially they are a period estimate that is benchmarked to the average annual population estimate over the given time period.
There are no one-year population estimates at the block group level, unless some 3rd party has developed something and I would not recommend ...
Not sure if a portal is useful, if it doesn't have the right data, but here's the Italy Open Data Portal
with 27k+ datasets:
from the Agency for Digital Italy: https://www.agid.gov.it/
Thanks for submitting your questions. I forwarded your questions to our helpdesk and received the following responses. I hope you find them helpful.
What is the best way to determine the concrete subset percentage [of
TIV students] used for a given measure? Is it a "cohort" column, like
Number of students in the family income cohort?
For some metrics ...