Rule of 72 - History

History

An early reference to the rule is in the Summa de Arithmetica (Venice, 1494. Fol. 181, n. 44) of Luca Pacioli (1445–1514). He presents the rule in a discussion regarding the estimation of the doubling time of an investment, but does not derive or explain the rule, and it is thus assumed that the rule predates Pacioli by some time.

A voler sapere ogni quantita a tanto per 100 l'anno, in quanti anni sarà tornata doppia tra utile e capitale, tieni per regola 72, a mente, il quale sempre partirai per l'interesse, e quello che ne viene, in tanti anni sarà raddoppiato. Esempio: Quando l'interesse è a 6 per 100 l'anno, dico che si parta 72 per 6; ne vien 12, e in 12 anni sarà raddoppiato il capitale. (emphasis added).

Roughly translated:

In wanting to know of any capital, at a given yearly percentage, in how many years it will double adding the interest to the capital, keep as a rule 72 in mind, which you will always divide by the interest, and what results, in that many years it will be doubled. Example: When the interest is 6 percent per year, I say that one divides 72 by 6; 12 results, and in 12 years the capital will be doubled.

Read more about this topic:  Rule Of 72

Famous quotes containing the word history:

    Tell me of the height of the mountains of the moon, or of the diameter of space, and I may believe you, but of the secret history of the Almighty, and I shall pronounce thee mad.
    Henry David Thoreau (1817–1862)

    Regarding History as the slaughter-bench at which the happiness of peoples, the wisdom of States, and the virtue of individuals have been victimized—the question involuntarily arises—to what principle, to what final aim these enormous sacrifices have been offered.
    Georg Wilhelm Friedrich Hegel (1770–1831)

    These anyway might think it was important
    That human history should not be shortened.
    Robert Frost (1874–1963)