Scoring: Brazil

Again a slightly tricky one because of the military government from the 60s-80s, so the numbers might be slightly off if there was a different Head of Government office during that time.

• Date of joining: 1945-10-24
• Expected count from Wikipedia (Getúlio Vargas onwards): 27?
• Number in Wikidata: 21
• PositionHolderHistory warnings: 27
• Score: 49/104 = 47% 156/270 = 58%