Poverty via PUMS and Poverty using table B17001

When I compute poverty status using the PUMS variable POVPIP <100 (percent) to create a variable "Below Poverty Level"  and "Above or equal to Poverty Level'  I get no missing data and a total population of 124,553 (OHIO CLEVELAND CENTRAL PUMA state ohio 39 puma fips 00906)  whereas ACS 2020 vintage 5 year table B17001 gives a total population of 120,938 with a universe of  "Population for whom poverty status is determined "  for the PUMA. So the PUMS data gives a difference of 3615.  Presumably the PUMS excess consists of "population for whom poverty status is NOT determined."  Does anyone know what PUMS variable needs to be used to set the 3615 individuals to "undetermined?"  Could these be group quarters people? https://www.census.gov/topics/income-poverty/poverty/guidance/poverty-measures.html  For example people in college dormitories don't have poverty status assigned.  ACS table B01001 (Age by Sex) gives a total population for the PUMA of 124,903. So the PUMS calculation for total population looks correct (I using the R survey package to handle weights)  I would expect that the PUMS and ACS detail tables would not give exactly the same total population because of disclosure avoidance Thanks in advance. Dave Dorer