If it was me I'd chop a zero off those N-year estimates. But that got me thinking, how often do they adjust these estimates? Was a "100 year flood" in 1950 les

If it was me I'd chop a zero off those N-year estimates. But that got me thinking, how often do they adjust these estimates? Was a "100 year flood" in 1950 less than in 2000, say? Obviously it'll be different for different areas, especially between countries, but still.