Introduced in 1961, POPS is apart of the NYC's Zoning Resolution to help combat the high dense areas in the city. There are a total of 73 Privately Owned Public Spaces, also known as POPS or bonus plazas, on the Upper East Side. All of them were created by developers in exchange for building bonuses, with the requirement that all should be properly maintained for public enjoyment and use. However, developers were not always keeping their end of the bargain and most POPS were not beneficial to the public. As time went on more requirements and specifications were stated so that developers could properly attribute to public use.