Sentence:  Sarkozy's total will be seen as a personal failure. It is the first time an outgoing president has failed to win a first-round vote in the <WSD>past</WSD> 50 years and makes it harder for Sarkozy to regain momentum. 
Meaning of the word marked with <WSD> tags:  Of a period of time: having just gone by; previous. (from 15th c.)