The transformation from local currency to USD uses the historical exchange rate at the mid-point of each reporting period. However, for volatile currencies, the mid-point rate can differ materially from period-end rates, affecting comparability. Should we disclose the exchange rate source and date used for each observation? (edited to fix a unit)

Elendil Ortiz Why does the Dakar series show such high volatility — swings of 20-30% year-on-year — while other West African cities are much steadier? The volatility could reflect genuine underlying variation, or it could indicate that Dakar's data comes from a less stable source or uses a less standardized collection method. Should we add a data-quality assessment or investigate the source?