--- slug: /en/sql-reference/aggregate-functions/reference/covarsamp sidebar_position: 37 --- # covarSamp Calculates the value of `Σ((x - x̅)(y - y̅)) / (n - 1)`. Returns Float64. When `n <= 1`, returns +∞. :::note This function uses a numerically unstable algorithm. If you need [numerical stability](https://en.wikipedia.org/wiki/Numerical_stability) in calculations, use the `covarSampStable` function. It works slower but provides a lower computational error. :::