Five parts in a will and a sixth prize added later: how the Nobel Prizes are divided

Background

Alfred Nobel signed his third and last will on November 27, 1895, at the Swedish-Norwegian Club in Paris.
The will directed that the interest on his fund be distributed annually as prizes to those who, during the preceding year, have conferred the greatest benefit to humankind.
The interest was to be divided into five equal parts, for physics, chemistry, physiology or medicine, literature, and for the person who has done the most or best to advance fellowship among nations, the abolition or reduction of standing armies, and the establishment and promotion of peace congresses.
The will assigned the prizes for physics and chemistry to the Swedish Academy of Sciences, the prize for physiological or medical achievements to the Karolinska Institute in Stockholm, the prize for literature to the Academy in Stockholm, and the prize for champions of peace to a committee of five persons to be selected by the Norwegian Storting.
Nobel wrote that no consideration be given to nationality when awarding the prizes.
His family opposed the establishment of the prize and the prize awarders he had named refused to do what he had requested in his will, and it was five years before the first Nobel Prize could be awarded in 1901.
A sixth award, the Sveriges Riksbank Prize in Economic Sciences in Memory of Alfred Nobel, is listed alongside the Nobel Prizes.