According to a study by the mayor's office, the city's municipal buildings accounted for nearly 3.8 million metric tons of greenhouse gas emissions each year and utilized 6.5 percent of the city's energy. The city's rate of energy consumption in NYC municipal buildings totaled nearly $1 billion each year, and accounted for about 64 percent of the city's greenhouse gas emissions. One of the main goals of Mayor Bloomberg's PlaNYC was to reduce greenhouse gas emissions by 30 percent by 2017.