Graduate student applications increased four-fold between 1985 and 1991.

Agricultural and fishing exports increased four-fold in value from 1974-77.

The risk of an accident increases four-fold when drivers are on the phone, the researchers said.

But during this time the Christians increased four-fold, and eventually reached forty per cent of the population.

Wall Street wages increased four-fold percent between 1977 and 1988, while all other wages rose 87 percent.

As evidence, the number of people employed by Griffin Technology increased four-fold between 2003 and 2007.

During the first years almost 3,000 employees were laid off and water bills increased four-fold.

We know it increased in size four-fold over the last several million years of evolution.

To be representative of the population diversity in the boardroom would have to increase four-fold.

Per-capita consumption of meat, eggs, and milk increased four-fold between 1978 and 2001.