It could take a little while for Trump to clean house on the US SES. As of the end of 2017 there was 7,800+ permanent employees. This report is from March 2018.

https://www.google.com/url?sa=t&source=web&rct=j&url=https://www.opm.gov/policy-data-oversight/data-analysis-documentation/federal-employment-reports/reports-publications/ses-summary-2017.pdf&ved=2ahUKEwiq6P-E7oTgAhVHNd8KHexZAPoQFjAGegQIBBAB&usg=AOvVaw0zoyRDtnzmJo-7eTrT0r6M