The Empire State Building is generally thought of as an American cultural icon. It is designed in the distinctive Art Deco style and has been named as one of the Seven Wonders of the Modern World by the American Society of Civil Engineers. The building and its street floor interior are designated landmarks of the New York City Landmarks Preservation Commission, and confirmed by the New York City Board of Estimate. It was designated as a National Historic Landmark in 1986. In 2007, it was ranked number one on the List of America’s Favorite Architecture according to the AIA.The building is owned by the 2800 investors in Empire State Building Associates L.L.C. The Empire State Building is currently undergoing a USD550 million renovation, with USD120 million spent in an effort to transform the building into a more energy efficient and eco-friendly structure.