It looks like Japan sees 1.5 million deaths/year, so 4000 deaths in half a year is about 0.5%. So this is outlier data, and it would not be at all surprising if

It looks like Japan sees 1.5 million deaths/year, so 4000 deaths in half a year is about 0.5%. So this is outlier data, and it would not be at all surprising if the overwhelming majority of them were childless. Whatever remains really cannot be enough to judge a society by.