Inflation in retirement
Quietly in the background, a destructive force is slowly at work eroding your retirement savings and diminishing your buying power; this force is inflation. By definition, inflation is a sustained increase in the general level of prices of goods and services, and it is measured as a percentage of increase (or decrease) in the annual prices of goods and services.
Basically, when the inflation rate rises (as it does most years), the value of your dollar decreases, meaning you can buy less with your dollar than you could before the inflation rate rose.