The answer probably depends greatly on the country and time period.
1370 and 1330 bc
58 years
Great Britain
Amonarchcan rule in a constitutional monarch as long as they are alive, Queen Elizabeth II is 84 and has ruled for 58 years and plans to keep ruling for many more years to come.
she was queen for 15 years.
Elizabeth I came to the throne in November 1558 and died in March 1603. She was queen for a little over 44 years.
they ruled from 1379 to 1504 :)
it has been 60 years since the queen has become queen.
1972 until the present day.
Cleopatra became queen for the first time at the death of her father when she was 18 years old. Her rule did not last long and she was exiled. She became firmly established as the queen in 47 BC when she was 22 years old.
Queen Elizabeth has reigned for sixty years.
She ruled England from 1558 to 1603 which is 45 years