Many government agencies and contractors require the use of Julian dates.
Examples of Julian Dates
The following are examples of Julian dates:Date Julian date ------------------------- Jan-01-1999 99001 Jan-10-1999 99010
Date Conversion Formulas
The following examples show how to work with serial number dates and Julian dates.To Convert a Serial Number Date to a Julian Date
Use the following Microsoft Excel 2000 formula to convert a serial number date to a Julian date=TEXT(Standard_Date,"yy")&TEXT((Standard_Date- DATEVALUE("1/1/"&TEXT(Standard_Date,"yy"))+1),"000")
To Convert a Julian Date to a Serial Number Date
The following formula converts a Julian date to a standard serial number date in Excel (the formula assumes that your date is in the 20th century):=DATE(1900+INT(Julian_Date/1000),1,MOD(Julian_Date,1000))
To Calculate the Number of Days Since January 1
To calculate the number of days since January 1 of the current year, use the following formula:=INT(((NOW()/365.255)-(YEAR(NOW())-1900))*365.255)
To Calculate the Number of Days Left in the Current Year
To calculate the number of days left in the current year, use the following formula:=(DATE(1+YEAR(NOW()),1,1)-(DATE(YEAR(NOW()),1,1)))- TRUNC(((NOW()/365.255)-(YEAR(NOW())-1900))*365.255)