The statistical record for many producing countries is very unsatisfactory. It's a fair generalization to say many third world countries don't consider providing statistics a top priority. U.S. coffee demand is price inelastic - buyers don't alter their purchases much because of rising or falling prices. Large price swings, though, such as those in 1994 and 1997, can shock coffee use downward. The CSCE's cocoa contracts are for 10 metric tons of cocoa.
Cocoa is slightly more tropical than coffee.
But, like coffee, cocoa comes from the seeds of the fruit of a tree. The yellow fruit can be harvested around six months after successful pollination of the tree's bloom. The seeds are removed and processed, leaving cocoa butter. Early season heavy rains are a typical culprit with cocoa as they hamper flowerings. But during harvest, if it's too wet, most producers don't have the technology to get the crop immediately indoors.