Hard numbers have been released by the US government agency that screens visas for high-skilled foreign workers, and they are not pretty.

Data made available by the US Citizenship and Immigration Services (USCIS) for the first time show that the widely made complaint about the visa program is true: a small number of IT outsourcing companies get a disproportionately high number of H-1B visas and pay below-average wages to their workers.

The H-1B program was put in the spotlight in April, when US President Donald J. Trump signed an executive order called “Buy American, Hire American” as part of his push to tighten immigration rules. Three months later, the USCIS formally disclosed the number of H1-B visas issued over the last two years by employer. Previously, the data were only available as estimates for companies petitioning for information, or by request under the Freedom of Information Act.

Almost 4,000 companies submitted H-1B visa applications in fiscal year 2016. The top 20 sponsors took home 37% of all visas issued . IT outsourcing companies made up the top five.

1 The number of visas issued is the total number of visa applications (I-129) approved by USCIS, including applications for new employment, change of job duties, change of location or application for an extension of H-1B validity period. New employment accounted for 39% of all H-1B approvals in FY2015.

The new data also give a more accurate picture of salaries of H-1B workers by employer. The top IT outsourcing companies on average paid much lower salaries to their workers.

The wage divide is largely a result of different education requirements of H-1B positions. H-1B visas are issued to workers with specialized skills which generally requires a Bachelor’s degree or higher. More than 98% of approved H-1B visa positions were awarded to workers with either a Bachelor’s or a Master’s degree in fiscal year 2016.

A closer look at the educations held by H-1B workers at companies like Google, Amazon and Intel—places with in-house tech staffs—show that more than 60% had Masters degrees. For most IT outsourcing companies, the majority of H-1B visa holders only had a Bachelor’s.

IT outsourcing companies score the most H-1B visas. As to where to find the most-skilled, highest-paid immigrant workers? The data show that IT outsourcing is the last place to look.