They calculate that in 2017 there were $1,504,191,364,000 in Federal spending guided by the census numbers, which is about $4,600 per capita.
In this paper [1] they look at some specific programs:
> Five grant programs administered by the U.S. Department of Health and Human Services (HHS) use the Federal Medical Assistance Percentage (FMAP), based on the 2010 Decennial Census population count, to determine reimbursements to and payments from each state government (totaling $286.1 billion in Fiscal Year 2015). The five FMAP-guided programs are Medicaid, the Children’s Health Insurance Program, Title IV-E Foster Care, Title IV-E Adoption Assistance, and the Child Care and Development Fund. In Fiscal Year (FY) 2015, reimbursements to and payments from state governments under these five programs totaled $286.1 billion (48.1% of all federal grants to states and 13.0% of all state budgets).In FY2015, 37 states forfeited a measurable amount of funds for each person missed in the 2010 Census.
> Among these 37 states, the median FY2015 loss per person missed in the 2010 Census was $1,091. FY2015 loss per person missed ranged from $533 for Utah to $2,309 for Vermont. The median state is Tennessee.
[1] https://gwipp.gwu.edu/sites/g/files/zaxdzs2181/f/downloads/G...
> Every year, federal and state governments use census data to allocate more than $675 billion toward public services and infrastructure [source: U.S. Census Bureau].
The link is to https://www.census.gov/content/dam/Census/library/visualizat....
