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<body class='hmmessage'><div dir='ltr'><p abp="4791">Hi Michael,</p><p abp="4791"> </p><p abp="4791">The <font face="Courier New,sans-serif" abp="4982">dsum</font> variable results from <font face="Courier New,sans-serif" abp="4983">datep, <font face="Calibri,sans-serif">contained</font></font> in the original <em abp="4984">data table </em><font face="Calibri,sans-serif" abp="4985">I give</font><em abp="4986">, </em>called <font face="Courier New,sans-serif" abp="4987">dt</font>. Thus, </p><p abp="4791"><font face="Courier New,sans-serif">dsum</font> is just to keep those dates contained in <font face="Courier New,sans-serif">datep</font> variable which correspond to 31st december or to the</p><p abp="4791">last register within each <font face="Courier New,sans-serif">id</font>.</p><p abp="4791"> </p><p abp="4791">Please, tell me for any further questions. I'm aware that the question is not easy.</p><p abp="4791"> </p><p abp="4791">Regards</p> </div></body>
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