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We start with a wonky distribution for $y$ (top); with increasing sample size, the distribution of $\overline{y}$ becomes more normally distributed, and as $n$ increases, more normal with smaller spread.
By taking samples of multiple variable values, and turning them into sample means, the original distribution (which was far from normal) morphs into the normal distribution, tucked about the mean of the original variable, with a standard deviation which decreases with increasing sample size.
Stat -> Tables -> Contingency ->
(then either data or summary, depending on what you have)