James Stock is on the committee that dates the rises and falls in the business cycle for the National Bureau of Economic Research.

VOA: special.2010.09.24

If properly managed, clearing and replanting trees in a 30-year cycle creates both a renewable source of energy and maximum rubber production.

VOA: standard.2009.09.13

The International Organization for Migration says most of Iraq's more than 1.5 million internally displaced people are caught in a vicious cycle of despair.

VOA: standard.2009.10.04

"But if you look into the Mekong delta, for example in Vietnam, it has shown the 30-year cycle, but the phase and amplitude is going up and then going up like that."

VOA: standard.2009.12.21

Galmudug regional government Minister of Planning Omar Mohamud warns that not implementing a long-term solution to the water problem will fuel the vicious cycle of droughts, hunger,and violence and keep the Somali people in the iron grip of poverty.

VOA: standard.2009.10.06