Age Harmonics are based on taking the locations of the planets/points at birth and multiplying them by the factor of your age.  As these factors change rapidly with minor adjustments of the birthtime, a very precise birthtime is needed to get reliable information from this technique. This technique is mainly employed in one of two ways. • For a specific time-period, the exact age at that time is used as the harmonic factor.  (to be multiplied by the natal positions) • For looking at years, we use the exact harmonic for that year and treat that chart as the “year’s chart.” Here, the allowable orb needs to be about 1° or so.  (though I tend to stretch it to 1° 21’ of arc, my normal transit orb) It is to be noted that the age harmonic chart produces a valid chart for events, both in and of itself (in terms of normal understanding of factors), as well as in aspect to natal factors.  Note that (for instance) a 0° 15’ error in the Midheaven (1 minute error of time), will result in a 7° 30’ error by the time one is 30 years old!  Since we are only considering around 1° aspects, one can see that obviously the system breaks, unless that birthtime is very tightly-defined.  (meaning seconds, not minutes)