The latest gauge on inflation released Wednesday morning showed that prices rose 4.2% over last year, based on the Consumer Price Index (CPI).

Why it matters: The gains were highest since September 2008. Prices jumped significantly compared to the start of the pandemic last year, when lockdowns drove down demand.

For context: Prices grew 2.6% year-over-year in March as the U.S. administered its 100 million COVID-19 vaccine dose, weeks ahead of schedule.

• Consumer prices have been more volatile over the past year than at any point in decades, Axios' Felix Salmon writes.

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