/src/main/java/net/finmath/time/daycount/DayCountConvention_ACT_ACT_ISDA.java
double daycountFraction = endDate.getYear( ) - startDateNextYear.getYear( ) - 1.0;
double daycountFraction = endDate.getYear ( ) - startDate.getYear ( ) - 1.0;
} @Override public double getDaycountFraction(final LocalDate startDate, final LocalDate endDate) { if(startDate.isAfter(endDate)) { return -getDaycountFraction(endDate,startDate); } <extra_id_0> LocalDate startDateNextYear = LocalDate.of(startDate.getYear()+1,Month.JANUARY,1); if(isCountLastDayNotFirst) { startDateNextYear = startDateNextYear.minusDays(1); } daycountFraction += getDaycount(startDate, startDateNextYear) / startDate.lengthOfYear(); LocalDate endDateStartYear = LocalDate.of(endDate.getYear(), Month.JANUARY, 1);