fined as:
<span class="math display" id="eq:definition-sample-variance">\[\begin{equation}
S^2_{Y} = \frac{\sum_{i=1}^n (Y_i - \overline{Y})^2}{n}
\tag{1.2}
\end{equation}\]</span>
So you simply subtract from each value the average value (the sample mean), and then raise each deviation to the power of 2. Then you add those squared deviations up, and divide the sum by the total number of observations. For the total goals scored, the variance is calculated as:
<span class="math display">\[\begin{align}
S^2_Y 