APPROX_PERCENTILE and ARBITRARY

Averages can be misleading. If one customer spends $100,000 and ninety-nine customers spend $100 each, the average is $1,089.90, which is far higher than what a typical customer spends. Percentiles tell you what typical really looks like. A percentile tells you what value a certain percentage of data falls below. The 50th percentile (median) is where half the values are below and half are above. The 95th percentile tells you the value that 95% of data falls below, which is useful for understanding outliers. Percentile Calculations Percentiles reveal data distributions that averages hide. They tell you what "typical" really means for your data. APPROX_PERCENTILE Median (p50) The median is the 50th percentile, which is the middle value. It's often more representative than the average because

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