What percentage of the energy flowing through primary producers is ultimately transferred to secondary consumers?

Energy transfer is the transmission of food energy from organism to the next which is illustrated as the food chain. Normally and typically, the autotrophs are the photosynthetic organisms that primary makes food for itself and for other organisms. Hypothetically, we can assume that about 6000 kilocalories per square meter per year these autotrophs can collect and store energy. Primary consumers like omnivores such as deer, cow, birds and etc. receive almost 10% as much from these autotrophs. Secondary consumers receive for as much as 1% of the total energy that was from the autotrophs.