The latest paper on the classification, now published in Review of World Economics 160(3): 873-903, or at https://doi.org/10.1007/s10290-023-00517-1, is David Cobham, ‘Monetary policy frameworks since Bretton Woods, across the world and its regions’ (available on open access).
An update to 2023, with the classification then covering 50 years, is due by late 2024 or 2025.
[First posted 4.12.23, corrected 5.12.23.]
Monetary Policy Frameworks 