To a cat, a window may look like a path to freedom, but it often leads to injury and death from upper story apartments. Each year, many cats fall from windows and balconies. The trauma sustained from a fall of over 2 stories (24 to 30 feet) is known as "high-rise syndrome." Studies done on cats that have fallen from 2 to 32 stories show that the overall survival rate is a surprising 90 percent. Strangely, cats that fall from a height under 6 stories have more severe trauma than those that fall from over 6 stories.
For more information, please read Highrise Syndrome in Cats