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<body class='hmmessage'><div dir='ltr'><p abp="5743">Excuse me,</p><p abp="5744"> </p><p abp="5745">One comment on my question: start and end variables are dates:</p><p abp="5746"> </p><p abp="5747"><font face="Courier New,sans-serif" abp="5791">DT <- data.table(ID=c(1,2,3),<br abp="5792"> start=as.Date(c("1985-01-01","1993-07-15","1993-05-17")),<br abp="5793"> end=as.Date(c("1992-05-01","1997-02-25","2002-01-01")),<br abp="5794"> value=c(7.8, 3.2, 20))</font></p><p abp="5747"><font face="Courier New" abp="5795"></font> </p><p abp="5747"><font face="Calibri,sans-serif">Thanks!!</font></p> </div></body>
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