There are no standard percentages for increases in rent. The average rent increase in 2014 was 3.6% nationwide, but the actual rates vary widely by location and market demand. Landlords can normally raise rent as much as they want, unless the properties are in municipalities that have rent control legislation.
Rent in New York City increased an average of 50.7% between 2009 and 2015. Landlords can normally raise rents after the lease expires. They must give tenants appropriate notice, even if the lease is month-to-month. As of 2015, cities with rent control include Los Angeles, California, Albany, New York and Buffalo, New York.