Assume the following is Bahrain's Balance of Payments data: \begin{tabular}{|c|c|} \hline \multicolumn{2}{|c|}{ Bahrain's Balance of Payments } \\ \hline Balance of Current Account & BD. Millions \\ \hline Bahrain Portfolio investment abroad & 5423 \\ \hline Net Error and Omission & 2511 \\ \hline foreign direct investment in Bahrain & 139 \\ \hline Bahrain purchases of foreign real estate assets & 1944 \\ \hline Official Reserve & 3521 \\ \hline \end{tabular} Find the value of the Official Reserve. Official Reserve =