139 new stations in Manhattan up to 110th Street and in Brooklyn between Red Hook and Prospect Park. The stations in the new installation were closer together than in previous phases because the previous phases had not fulfilled National Association of City Transportation Officials' recommended bike share-station density of . Some residents of Park Slope were outspoken in opposition to the loss of car parking. One month later, on September 13, 2016, the system saw 64,672 trips, the highest recorded in one day at the time. After the December 2016 announcement of a further expansion to Harlem and Astoria, some city politicians proposed expanding the system further to the Bronx and Staten Island. By the end of 2017, Citi Bike planned to double its bike fleet to 12,000, with the possibility that some of the expansion could be publicly funded. On May 18, 2017, Motivate presented a proposal to expand the system in all five boroughs, including adding new stations to the Bronx and Staten Island, without any public funding. To make up for the lost tax funding, Motivate asked the city to waive fees charged for placing stalls inside former parking spots, as well as redesigning the payment hierarchy and possibly adding more ad space on pay stations. The 140 new stalls and 2,000 new bikes in Harlem, Crown Heights, Prospect Heights, Long Island City, and Astoria were installed in September 2017. The system saw its 50 millionth rider in early October 2017, as the new stalls were being activated. The new docking stations in Brooklyn led to an imbalance in the number of bikes in certain neighborhoods, since there were more bikes being docked in lower-elevation areas such as Downtown Brooklyn, while fewer riders docked bikes in high-elevation neighborhoods such as Prospect Heights and Crown Heights. Dockless and phase 3 expansion In 2018, officials proposed dockless bike sharing for the Citi Bike network, which would allow bikes to be rented without being tethered to docks. This was proposed after several bike sharing companies announced their intent to operate in New York City. In early August of that year, the dockless bike-sharing company Spin had started a dockless operation in the Rockaways, but had been told to cease and desist operations by the NYCDOT, which had licensed Citi Bike as the only official bike-share operator in New York City. Spin, intending to compete with Citi Bike with lower per-half-hour