Recovering the sample variance from a sum of squared pairwise differences

For a given data set $\{x_1, x_2, … , x_n\}$, where $n = 100$, it is known that $$\frac{1}{2000}\sum_{i=1}^{n}\sum_{j=1}^{n}(x_i - x_j)^2 = 99$$ Let us denote $\bar{x} = \frac{1}{n}\sum_{i=1}^{n} x_i$ The value of $\frac{1}{99}\sum_{i=1}^{n}(x_i - \bar{x})^2$ is __________ . (Answer in integer)