Have behaviours become more inflationary?

Econometric models estimated on past data are often used to predict future wages and inflation. But there is a high risk of error if behaviours have become more inflationary in the recent period (leading wage growth and inflation to be underestimated), stripping estimations based on past behaviour of their relevancy for forecasting the future . The possible appearance of inflationary behaviours can be examined by looking at whether behaviours estimated econometrically on the past (wage and price formation) explain the recent period. We find that over the period 2021-2022, econometric models using past data underestimate: Wage growth in the United States; Price growth in the United States and the euro zone.