Prospero says that it has been twelve years since he was deposed and landed on the island. If he rescued Ariel immediately afterward, then Ariel has been his servant for twelve years. (He had been imprisoned in a tree for the previous twelve years.)
Twelve years
"The Vancouver Movers company is a full service moving company in Portaland, Washington. They are members of the BBB and have been in business for twelve years, since 1989."
Friends Reunited has been online for over twelve years. They have launched on July 1, 2000. Since then, it has collected over 23.8 million users online.
how many years has it been since 1997
It has been 525 years since 1492.
How many years have there been since 1776?
it has been 52 years since 1958
There have been 15 leap years since 1955:195619601964196819721976198019841988199219962000200420082012There have been 15 leap years since 1955:195619601964196819721976198019841988199219962000200420082012There have been 15 leap years since 1955:195619601964196819721976198019841988199219962000200420082012There have been 15 leap years since 1955:195619601964196819721976198019841988199219962000200420082012There have been 15 leap years since 1955:195619601964196819721976198019841988199219962000200420082012There have been 15 leap years since 1955:195619601964196819721976198019841988199219962000200420082012There have been 15 leap years since 1955:195619601964196819721976198019841988199219962000200420082012There have been 15 leap years since 1955:195619601964196819721976198019841988199219962000200420082012There have been 15 leap years since 1955:195619601964196819721976198019841988199219962000200420082012There have been 15 leap years since 1955:195619601964196819721976198019841988199219962000200420082012There have been 15 leap years since 1955:195619601964196819721976198019841988199219962000200420082012
Impossible to answer since you don't state what condition it is in.
It has been 53 years since 1969.
Now is 2012. It's been 512 years since the year 1500. It's been 413 years since year 1599.