Premise: U.S. President Donald Trump on Monday called for tighter restrictions on immigration in the wake of the terrorist attack in New York City carried out by a Bangladesh native living in the U.S. "America must fix its lax immigration system, which allows far too many dangerous, inadequately vetted people to access our country," Trump said in a written statement quoted by USA Today.
Hypothesis: Once the reference point has been established, the Price Index value of every other city in the database is calculated by comparing their cost of living to the cost of living in Prague.