Mock 2010 Q13 daily Var problem

Mock 2010 Q13

the answer is

Asuming 250 trading days per year,if daily Var at 95% confident level is 1 million,over one year a daily loss exceeding 1 million should occur approximately 5% of 250 days or 12.5 days.

i can not understand this answer .what does it talking about?

historical method

250 x 5% = 12.5 days