However, in the 30 year period between 1980 and 2010, the average was just 22 days.

The project is expected to cost £30 million over a five year period.

The book takes place over a period of 43 years, from 1706 to 1749.

For a period of seven years between 1869 and 1875 the race was not held.

Over a period of five years, between 1979 and 1984.

His studies in the University was for a period of five years, from 1953 to 1958.

The couple had 13 children over a period of 22 years.

"All have been working for a period of over 8 to 10 years or longer."

The course would run for a period of two years.

You must keep them for a period of at least four years.