Secondary progression chart
Secondary progression is a timing technique based on the principle that “one day equals one year.” The first day after birth symbolizes the first year of life, and the ninetieth day the ninetieth year. For example, for your 30th year, the sky 30 days after your date of birth is calculated and that chart is compared with your birth chart. This technique is used to interpret a person's inner development and slowly changing psychological themes, while transits describe external events and triggering periods more.
The progressed Sun advances about one degree a year and changes sign roughly every 30 years; these shifts are interpreted as periodic changes in one's sense of identity. The progressed Moon advances about 12-13 degrees a year, changes sign about every 2.5 years and shows phases in emotional needs; the progressed Moon's phase relative to the natal Sun is also read separately. Mercury and Venus can change sign as well, while the outer planets stay almost in place. Secondary progressions require an accurate birth time, because the progressed Moon and Ascendant are sensitive to errors in the time.
