Vedic astrology is an ancient behavioral analysis and forecasting system. Unless you were born between about the 15th and 20th of the month, you will find your "Western" Sun has most likely moved back by one sign in a Vedic astrological chart.
Eastern Astrology differs from Western astrology which most of us are more familiar with. The differences in astrological approaches are reflected in the Eastern use of a constellational, rather than solar, chart analysis.