In the previous lesson we mentioned that in reviewing a price graph it is possible to note certain changes in the price of securities associated with major market dates. What if, instead of focusing on a market date in the query, you described the price movement of the security as a condition that had to be met in order to SHOW our defined attribute. In other words what if you isolated those dates that made certain price movements and reviewed the price action of our security following the defined trend? This sort of analysis is done all the time in market industry periodicals. It is not uncommon for the Wall Street Journal or other newspaper to carry headlines that read "Stocks Plunge 300 points, Year's Worst Fall…Should We Expect a Rebound?". It would be interesting to isolate those dates in the past when the market sold off by a similar amount to see what happened to the price of the securities.