There are two related bugs in age display (e.g. on artist pages):

• If an entity with a known begin year is ended, but with unknown end date, age will be displayed as if the entity was still active. (This is not much of a problem, but not as intended.)
• If an entity with a known begin year is ended, and some part of the end date is known (e.g. month), but not the year, an ISE will occur. This is because an attempt is made to calculate the difference between end and begin years, while the end year is undefined.