Adults spend about 50% in stage 2 and approximately 20% in REM sleep. When we sleep we go through different stages of the dream, it is divided into 5 phases; stage 2 occurs when we have a light sleep, heart rate, and breathing decrease. In the REM stage there is a lot of brain activity and immobility of the body, in this stage of the dream is when we dream.
I hope this information can help you.