The COVID-19 pandemic affected the entire global economic system, including currency exchange rates. The main objective of this study is to assess the similarity between time series of currency exchange rates before and during the COVID-19 crisis. In addition, the study aims to examine the relationship between the exchange rates of currencies and the COVID-19 time series in particular countries. The Dynamic Time Warping (DTW) method was applied to check if changes in the exchange rates were related to the spread of COVID-19, and if they were, to what extent it was so. The use of the DTW allows the calculation of the distance between analysed time series. In this study, it made it possible to group the analysed currencies according to their change relative to the pandemic dynamics. The study is based on data from the Stooq and Our World in Data websites. Data on the 17 studied currencies denominated in the New Zealand dollar came from the period between 1 January 2019 and 10 November 2021, and the COVID-19 data from the period between 1 March 2020 and 10 November 2021. The results demonstrate that exchange rates evolved differently in all the three analysed periods: the pre-pandemic period and the first and the second phase of the pandemic. The outbreak of the pandemic led to the concentration of most currencies around the US dollar. However, when the economies unfroze, a polarisation of the currency market occurred, with the world’s major currencies clustering either around the US dollar or the euro.
currency exchange rates, COVID-19 pandemic, Dynamic Time Warping, DTW
C58, C32, C38
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