How much percent of energy goes to the next food level?

Energy Pyramids – shows the magnitude of the energy flow or productivity at successive levels.
The law of the energy pyramid (10 percent law), according to which, on average, about 10% of the energy delivered to the previous level of the ecological pyramid passes from one trophic level through food chains to another trophic level. The rest of the energy is lost in the form of thermal radiation, for movement, etc. Organisms, as a result of metabolic processes, lose about 90% of all energy in each link of the food chain that is spent on maintaining their vital functions.