The Achievement number, more often called the Maturity or Reality number, is formed by adding the Life Path, drawn from the birth date, to the Expression, drawn from the full name, and reducing the two-digit total. Where the Life Path describes the road travelled and the Expression the talents brought to it, the Achievement is read as the direction the two converge upon in the second half of life, the underlying goal that surfaces, in the usual account, from around the late thirties onward, once the earlier lessons have been worked through. It is the number of what a life is ultimately for, in the numerological reading, emerging only as maturity sets in.
This atlas's own sources place the Achievement, or Maturity, number among the later elaborations of the chart, generally credited to Florence Campbell's 1931 Your Days Are Numbered and to Juno Jordan's 1965 systematisation rather than to Balliett's original 1908 publication or to Cheiro's 1926 Book of Numbers, both of which worked with the Life Path and Expression separately rather than combining them into a single later-life figure. Not every modern numerologist layers a further figure onto the Life Path and Expression at all: Dan Millman's widely read 1993 book The Life You Were Born to Live works from the Life Path number alone, without any Achievement or Maturity figure, a reminder that the combined later-life number described throughout this family of articles is a particular, mid-century elaboration rather than a feature of modern numerology as such.