The General Schedule (GS) payscale is the federal government payscale used to determine the salaries of over 70% of federal civilian employees.
Under the GS payscale, an employee's base pay depends on two factors - the GS Paygrade of their job, and the Paygrade Step they have achieved (depending on seniority or performance). This base pay is then modified based on a "Locality Pay Adjustment", which adjusts the GS payscale based on cost-of-living in different areas within the United States.
Puerto Rico does not contain any Locality Pay Adjustment areas, so all federal employees in the state are paid the "Rest of US" GS rates.
* For some high-paygrade workers pay under the GS scale may be capped at $155,500, which is the SES (Senior Executive Scale)'s Level 4 pay for the current year (5 U.S.C. 5304 (g)(1)).