But "crash" is relative and continuous. The article defined what's traditionally been defined as a "crash". It's like "unemployment": there may ways to measure,

But "crash" is relative and continuous. The article defined what's traditionally been defined as a "crash". It's like "unemployment": there may ways to measure, each with different strengths and tradeoffs, but there are one or two traditional "common" metrics. Politicians tend to cherry-pick different metrics over time to fit their narrative of making them look good and the "enemy" bad.