Bair Krishnan The restatement in 2008 affected the North region disproportionately, with revisions ranging from 3% to 18%, while the South region saw only minor adjustments. This asymmetry suggests either a localized data-quality issue or a genuine structural change in the North. Should we document this as a known comparability break, or should we attempt to restate the entire time series consistently?

Looking at the exchange-rate adjustment, it's applied uniformly to all currencies, but highly volatile currencies might need a different timing (e.g., end-of-month vs. average-of-month) to avoid artifacts. Should we differentiate the exchange-rate timing by currency volatility?