In places where the climate is very moist throughout the year at least 79 inches a year are tropical rain forests.
In other tropical areas where annual precipitaion is less but is still enough to support trees are called tropical dry forests.
The food and Agriculture Organization estimate an average annual loss in forests of 1.1% per year. And in some areas such as West Africa have a loss greater than 2% per year.
If this rate of deforestation, which represents a worldwide annual loss of 41.8 million acres continues, tropical forests will be gone by 2500.