1977 to present. All hardship I ever suffered was during my lifetime, not before. 
This has much greater impact on me than the 14th Century. I must agree with Reno, for us WW2 and WW1 and recent wars are much more present than wars of the past.
so 1300-1399... as the worst period. This is again limited to an European View: The Aztecs probably enjoyed their live much more in that time. The Conquest of Mexico by Cortez might have been THEIR worst century.

This has much greater impact on me than the 14th Century. I must agree with Reno, for us WW2 and WW1 and recent wars are much more present than wars of the past.
so 1300-1399... as the worst period. This is again limited to an European View: The Aztecs probably enjoyed their live much more in that time. The Conquest of Mexico by Cortez might have been THEIR worst century.