Western (Tropical) astrology measures planetary coordinates relative to the moving Vernal Equinox (the Sun's seasonal position), which precesses backward against the stars by roughly 1 degree every 72 years. In contrast, Vedic (Sidereal) astrology roots its coordinates in the actual observable constellations fixed in the celestial sky.
Official Lahiri Ayanamsa (~24° Shift): Sanctioned by the Government of India Calendar Reform Committee (1955), Lahiri (Chitra Paksha) fixes the star Spica at exactly 180 degrees. At present, the offset is approximately 24°10'. Consequently, your Vedic rising sign (Lagna) and Moon sign (Chandra Rasi) typically sit one full zodiac sign earlier than in Western astrology.