{
 "id": "poland-1989-1990",
 "country": "Poland",
 "currency": "Złoty",
 "periodStart": "1989",
 "periodEnd": "1990",
 "peakInflation": "77.3%",
 "peakMonthlyPct": 77.3,
 "peakMonth": "January 1990",
 "doubling": "36.8 days",
 "hkEpisode": "Oct 1989 – Jan 1990",
 "currencyReform": "1 new złoty = 10,000 old (1995)",
 "cause": "End of communism, indexed wages, a deficit paid with money",
 "resolution": "Balcerowicz Plan (1 Jan 1990): budget fix, dollar anchor",
 "url": "https://hyperinflation.rogzy.org/poland-1989-1990/",
 "summary": "As communism ended in 1989, controlled prices were freed while wages stayed indexed and the budget was financed by the central bank. Prices rose more than 50 % a month from October 1989. The peak was 77.3 % in January 1990, doubling every 36.8 days (H&K): the month the Balcerowicz Plan freed nearly every price at once, made the złoty convertible and fixed it to the dollar. After that month the hyperinflation was over.",
 "timeline": [
  {
   "date": "Sep 1989",
   "event": "Tadeusz Mazowiecki's government; Leszek Balcerowicz becomes finance minister."
  },
  {
   "date": "Oct 1989",
   "event": "Monthly inflation passes 50 % (H&K start). On 6 October the plan is presented on television."
  },
  {
   "date": "Dec 1989",
   "event": "The Sejm passes ten laws, signed on 31 December."
  },
  {
   "date": "Jan 1990",
   "event": "Peak 77.3 % (H&K); real wages fall more than 40 % over two months."
  },
  {
   "date": "1995",
   "event": "The new złoty removes four zeros."
  }
 ],
 "banknotes": [
  {
   "label": "10,000 złotych (1 Dec 1988)",
   "image": "https://hyperinflation.rogzy.org/assets/bills/web/10k_Zlotych.jpg"
  }
 ],
 "exchangeRates": {
  "unit": "Złoty per 1 USD",
  "approximate": true,
  "notes": "Hyperinflation from October 1989 to January 1990, peak 77.3% in January 1990 (Hanke & Krus). From 1 January 1990 the złoty was fixed to the dollar (9,500 in 1990) under the Balcerowicz Plan. In 1995, 10,000 old złoty became 1 new złoty. Approximate series, kept for its shape; individual points are not sourced one by one.",
  "sources": [
   "National Bank of Poland",
   "IMF - Moderate Inflation in Poland"
  ],
  "points": [
   {
    "date": "1989-01",
    "rate": 510
   },
   {
    "date": "1989-03",
    "rate": 780
   },
   {
    "date": "1989-06",
    "rate": 1200
   },
   {
    "date": "1989-08",
    "rate": 2150
   },
   {
    "date": "1989-10",
    "rate": 4500
   },
   {
    "date": "1989-12",
    "rate": 6500
   },
   {
    "date": "1990-01",
    "rate": 9500
   },
   {
    "date": "1990-06",
    "rate": 9500
   },
   {
    "date": "1990-12",
    "rate": 9500
   },
   {
    "date": "1991-05",
    "rate": 11100
   }
  ]
 },
 "sources": [
  "Hanke & Krus (2012) — episode, peak, doubling time.",
  "Wikipedia, \"Polish złoty\" (read 2026-10-05): https://en.wikipedia.org/wiki/Polish_z%C5%82oty",
  "Wikipedia, \"Balcerowicz Plan\" (read 2026-10-05): https://en.wikipedia.org/wiki/Balcerowicz_Plan"
 ],
 "licence": "Text and data: MIT (c) 2026 Rogzy. Banknote images (c) David St-Onge, not covered by the MIT licence."
}