The natal chart shows your whole life, but how do you know what year certain events will take place like marriage for example? Once you're born, your chart starts "progressing" or ticking off like a timer. A degree per year actually. This evolution of your chart then tells you the approximate year events take place such as what year you marry, have children, go to college (if you do go), and so on. So in order to know what year events promised by the natal chart happen, that's why you also calculate the "progressions", or compare the natal chart to the progressed chart. The same thing for events, business or even city charts - the progressed chart shows you the evolution of the natal, or base chart. Events or changes in the progressed chart are very difficult to change as these fall heavy into the destiny category. You can't change them like you can change a solar return simply by being in a different city on that day. Progressions are etched in stone in other words. www.theadultastrologer.com