A helper function to calculate dates a year apart, starting from a given date for a set number of years. Useful for delimiting a specified time interval into a discrete number of years.
determine_yearly_endpoints(date, num_years, direction = "forwards")Either the starting date of the time interval (when direction is 'forwards')
or the ending date (direction is 'backwards').
The number of years of the time interval.
A string indicating whether the parameter date represents
the opening or closing interval. Must take values either 'forwards' or 'backwards'.
A vector of dates delineating complete years of registry data.