I've found some employment statistics (but not divided):

1999 from Gloria Brame:
Salaried Employee 38%
Middle Management 15%
Self-employed 14%
Unemployed/Student/Retired 8%
Upper Management 6%
Temporary or Contract Worker 6%
CEO / Person in Charge 5%
Consultant 5%

2001 from Datenschlag.org (germany):
Student 28%
Salaried Employee 22%
Self-Emploeyd 17%
Middle Management 11%
Technician, Craftsman, Worker 8%
Official/Appointee 5%
not specified 9%