Hillary Clinton’s plans to expand the number of refugees admitted to the United States could equate to 620,000 refugees over a single four-year term in office, at a lifetime cost to the taxpayer of over $400 billion, according to an analysis by the Subcommittee on Immigration and The National Interest.

The analysis, released Monday, charges that Clinton’s plan to admit at least 65,000 Syrian refugees, above the existing annual refugee stream, could find a Clinton presidency admitting 155,000 new refugees each year.

Assuming Clinton’s desire to bring in 65,000 Syrian refugees is in addition to the Obama Administration’s current goal of admitting 10,000 this fiscal year (out of 85,000 total refugees), that would amount to an increase of 55,000 refugees. 55,000 on top of 85,000 totals 140,000 refugees. The Obama Administration’s target for FY 2017 is actually 100,000 refugees, meaning that adding 55,000 refugees to that would result in 155,000 refugees each year. Due to statutory flaws in our Refugee Admissions Program, the number could be as high as Hillary Clinton desires. Assuming her goal is to admit 155,000 refugees each year during a hypothetical first term in office, a Clinton Administration would admit at least 620,000 refugees in just four years – a population roughly the size of Baltimore.

Beyond the national security concerns of admitting 65,000 refugees from the terrorism hot-spot of Syria, the Subcommittee highlights that such admissions are not without cost to the taxpayer. Unlike other types of immigrants, refugees are immediately eligible for welfare benefits upon admission to the U.S. and continue to be able to access benefits as they progress to permanent residency and citizenship.

Undoubtedly, the resulting costs of admitting the refugees under Clinton’s plan will be enormous. Robert Rector at the Heritage Foundation has estimated that the total lifetime cost of admitting 10,000 refugees is $6.5 billion. This estimate encompasses costs to taxpayers at the federal, state, and local levels. Using Mr. Rector’s numbers as a baseline, admitting 155,000 refugees in one year would result in a total lifetime cost to the taxpayers of $100,750,000,000. If those levels were sustained over the course of four years – a hypothetical first term in office – the lifetime cost to the taxpayers according to Mr. Rector’s analysis would be $403 billion.

The Subcommittee adds that the estimated $403 billion price tag on Clinton’s refugee resettlement plans do not take into account the foreign nationals who are granted asylum status nor does it include the cost of family reunification policies, wherein refugees are able to bring their family members once admitted to the U.S.

Indeed, if an individual refugee’s spouse or unmarried children were not admitted at the same time as the refugee, they are eligible to “follow-to-join” and be admitted to the United States for two years after the individual refugee’s admission. One year after being admitted to the United States, refugees are eligible to adjust to Lawful Permanent Resident status (i.e. obtain a “green card”), enabling them to petition for additional family members. And assuming that a refugee becomes a Lawful Permanent Resident, he or she is further eligible to naturalize five years after being admitted to the United States, enabling them to bring in additional relatives. Thus, the total cost of admitting a certain number of refugees in any given year could be even higher than Mr. Rector predicts.

The Subcommittee on Immigration and The National Interest is chaired by Sen. Jeff Sessions (R-AL), a policy advisor to Clinton’s presumptive opponent, Donald Trump.