Simple math (numbers are made-up): start with 500,000 jobs. Eliminate 50,000 jobs in industry, commerce and service industries. Eliminate 50,000 government jobs (police, firefighters, teachers, bureaucrats). Total job loss is 100,000. Create 90,000 new jobs in industry, commerce and service industries. Net reduction in jobs is 10,000.

The word net means what is left when you add and/or subtract changes from the figure you started with. A net reduction in population means that deaths exceed births, not that there are no births. A net reduction in jobs means that job losses exceed gains, not that there are no gains.