Compared with patients who avoided these painkillers, those who took an NSAID had a 2.4-fold higher risk of a major bleed and those who took aspirin had a 1.5-fold higher risk. Even though [this warning about major bleeds with NSAIDS or aspirin] is on the warfarin label. . .
5 years. A decade means 10 years, so to find out how many years are  in half of a decade you would simply divide 10 by 2, which is 5.
A century (from the Latin centum, meaning one hundred; abbreviated c.) is a period of 100 years. Centuries are numbered ordinally in English and many other languages. For example, the 17th century refers to the years from 1601 to 1700. A centenary is a hundredth anniversary or a celebration of this, typically the remembrance of an event which took place a hundred years earlier.