Date Calculator: Add to or Subtract From a Date – Results

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Principles for Calculation of progression
Rule 1
Once the major period of planet begins the concerned planet would travel over
all the twelve houses
Starting from its position in the sign at the time of birth through progression.
Suppose the planet is at 10 degree in Libra in the birth chart. It would start
progressing from 10 degree Libra. The planet Progress to Scorpio, Sagittarius,
Capricorn, etc till it enters Libra at O degree and reaches 10 degree in the sign
again.
The major Vimshottari period shall come to an end when the planet through
progression has returned to its natal Position respectively.

Principles for Calculation of progression
Rule 2
A planet that is in direct motion in the birth chart shall always progress
(Forward motion). Such a
Planet should move from a sign to the next sign. If for example, it is in Cancer it
should move to Leo, Virgo, Libra etc.
A planet that is retrograde in the birth chart shall always regress (Backward
motion). Such a planet if in Cancer should move to Gemini, Taurus, Aries etc.
The Sun and Moon shall invariably progress. Rahu and Ketu shall invariably
regress.