Make it up as you go along. Age is not a distinct factor but oneof the things that MIGHT be considered when setting goal, analyzing one's needs and risk tolerance. I've seen 90 year olds 100% invested in stocks and 30 year olds 100% invested in bonds. How much did age come into play? Zilch. For most, it is not a factor. 
Of course if you believe it is an important factor, you would never have considered how it might impact ones ability to trade the market daily wuld you?
By the way, I'd be willing to wager the move in the C$ - U$ relationship has benefitted me more.
My portolio is off 1.7% from its all time high. Purrfect.