Can someone explain how this sparkline works on this trend on Excel?

Year \begin{tabular}{|l|l|} \hline 2015 & 138,103.00 \\ \hline 2016 & 115,943.00 \\ \hline 2017 & 121,295.00 \\ \hline 2018 & 128,681.50 \\ \hline 2019 & 134,742.50 \\ \hline 2020 & 134,949.50 \\ \hline 2021 & 140,349.50 \\ \hline 2022 & 120,964.50 \\ \hline 2023 & 124,263.50 \\ \hline \end{tabular} Year \begin{tabular}{|l|l|} \hline 2015 & 138,103.00 \\ \hline 2016 & 115,943.00 \\ \hline 2017 & 121,295.00 \\ \hline 2018 & 128,681.50 \\ \hline 2019 & 134,742.50 \\ \hline 2020 & 134,949.50 \\ \hline 2021 & 140,349.50 \\ \hline 2022 & 120,964.50 \\ \hline 2023 & 124,263.50 \\ \hline \end{tabular}