In a nutshell - if a fleet of roughly 20 airframes uses kit at a steady state of 2 - 3 widgets per year, and 2 years kit is held, then the department would hold 60 widgets.
If said fleet is reduced to 2 useable airframes, and useage rates remain the same, then suddenly the Department has 60 widgets, and 20-30 years worth of stock.
The stats look bad until you consider that equipment is purchased some time ahead based on planned maintenance routines and useage rates, and is often purchased prior to political decisions to reduce, or remove airframes from service.
Great tabloid headline though!