Return the (signed fractional) number of years between the specified beginDate and endDate. If beginDate <= endDate, then the result is non-negative. The behavior is undefined unless firstDate() <= beginDate <= lastDate() and firstDate() <= endDate <= lastDate(). Note that reversing the order of beginDate and endDate negates the result; specifically, |yearsDiff(b, e) + yearsDiff(e, b)| <= 1.0e-15 for all dates b and e.
Declared in <bbldc_daterangedaycount.h>
virtual
double
yearsDiff(
bdlt::Date const& beginDate,
bdlt::Date const& endDate) const = 0;