There must be a method of calculating the price of a stock based on the shares tradedat particular prices. for an exaggerated example, lets say a stock traded 3 millionshares in a single day. assume 2,000,000 shares traded at $0.90 while the last tradeof the day was for 1,000,000 shares at a price of $1.00. question: did this stock tradeat a minimum of $1.00 that day. if you look at the closing price, you might assume thatthe stock traded at $1.00 and meets the minimum standard. but if you weighted theprices for each trade based on the number of shares traded, you can see from theexample above that the price for the day averaged to something closer to $0.93 (33%of shares x $1.00 + 66% of shares x $0.90). im not sure of the exact method used bys&p/tsx, but the above information gives you an approximate idea.