When did Victoria, Crown Princess of Sweden, become heir apparent to the Swedish throne?

Victoria, Crown Princess of Sweden is the heir apparent to the Swedish throne, as the eldest child of King Carl XVI Gustaf. If she ascends to the throne as expected, she will be Sweden's fourth queen regnant (after Margaret, Christina and Ulrika Eleonora) and the first since 1720.

Victoria was born on 14 July 1977 at 21:45 at the Karolinska Hospital in Solna, Stockholm County, Sweden, and is the oldest child of King Carl XVI Gustaf and Queen Silvia. She is a member of the House of Bernadotte. Born as a princess of Sweden, she was designated crown princess in 1979 (SFS 1979:932) ahead of her younger brother. Her place as first in the line of succession formally went into effect on 1 January 1980 with the parliamentary change to the Act of Succession that introduced absolute primogeniture (the right, by law or custom, of the firstborn legitimate son to inherit his parent's entire or main estate).