It's possible to define a relative date manually; this is not something that's commonly done. All relative dates start with the letter "
R". This is then followed by:
W= start of week, w = end of week,
M= start of month,
m= end of month,
Q= start of quarter,
q= end of quarter,
Y= start of year,
y= end of year,
F= start of fiscal year,
f= end of fiscal year
RDM-15decodes as "Relative", "Days", "Start of month", -15 = "Subtract fifteen days from the current date, then adjust to the beginning of that month."
RWy+4decodes as "Relative", "Weeks", "End of year", +4 = "Add four weeks to the current date then adjust to the end of that calendar year."
RD30decodes as "Relative", "Days", +30 = "Add thirty days to the current date."