@DOY — returns the day of the year for the specified date. January 1 will return 1; December 31 will return 365 or 366. The date may be in any input date format supported by this plugin, and it must be a valid date within the supported range.

Syntax:
%@DOY[date,infmt]

datethe date to examine; if omitted, uses today’s date
infmtthe input date format, used to interpret ambiguous dates