Citation counts for each year were normalized to the maximum citation count of the time period using the equation $C_{i}^{Norm}=\frac{C_{i}}{C^{max}}$, where $C_{i}$ is the citation count in year $i$ and $C^{max}$ is the maximum citations in a 5-year period. To evaluate trends before and after Wikipedia inclusion, a 'citation propensity' metric was utilized. First, the normalized random citation count ($R_{i}^{Norm}$) was calculated as $R_{i}^{Norm}=\frac{R_{i}}{R^{max}}$, where $R_{i}$ is the random citation count in year $i$ and $R^{max}$ is the random maximum citation count in the 5-year period. Finally, propensity was calculated as $P_{i}=\frac{C_{i}^{Norm}}{R_{i}^{Norm}}$. A propensity ($P_{i}$) equal to 1 indicates the citation count matches chance expectations, greater than 1 indicates higher than expected citations, and less than 1 indicates lower than expected citations.