It is generally not intended to cover the entire life of the Solar System; usually a short-duration time span, perhaps a few centuries, is represented to high accuracy.
The latest releases include DE430 which covers planetary and lunar ephemeris from Dec 21, 1549 to Jan 25, 2650 with high precision and is intended for general use for modern time periods .
DE431 was created to cover a longer time period Aug 15, -13200 to March 15, 17191 with slightly less precision for use with historic observations and far reaching forecasted positions.
The ephemeris must be calculated strictly in accordance with this set, which represents the most current knowledge of all relevant physical forces and effects.
A fundamental ephemeris is the basis from which apparent ephemerides, phenomena, and orbital elements are computed for astronomical, nautical, and surveyors' almanacs.
Phenomena are events related to the configurations of Solar System bodies, for instance rise and set times, phases, eclipses and occultations, and have many civil and scientific applications.
From the mid 20th century, work began on numerical integration of the equations of motion on early computing machines for purposes of producing fundamental ephemerides for the Astronomical Almanac.