The difference is celestial longitude between the sidereal sign and its corresponding tropical sign. An exact value of 24 degrees was computed in 1950 by astrologers Fagan and Bradley. Because of precession the value of the ayanamsa increases by 1.4 degrees per 100 years. A Sanskrit term that is also used to indicate the difference in arc between the starting point of the Tropical and the Sidereal zodiacs. An astrological chart referred to the Tropical zodiac may be converted to the Sidereal zodiac by subtracting the ayanamsha for the same date. Several different ayanamsas are currently in use.