Every year around 1 billion Valentine cards are sent. After Christmas it's a single largest seasonal card-sending occasion.
In Finland, Valentine's Day is called "Ystävänpäivä" which translates into "Friend's day".
40% of people who are rejected in romantic love slip into clinical depression.
It's possible to die from a broken heart; it's called Stress Cardiomyopathy.
Close to 110 million roses (mostly red) will be purchased and delivered around Valentine's Day in the U.S.