The article introduces a new method to break down changes in income uncertainty over time and with economic ups and downs. By analyzing spending data, the method can identify both long-lasting and temporary factors affecting income. The study uses computer simulations to demonstrate the method's reliability in dissecting income risk. It applies this approach to study income uncertainty in Britain from the late 1970s to the late 1990s, revealing peaks in long-term income shocks during the mid-1980s and early 1990s.