Potential buyers have been grappling with a limited supply of houses, more expensive homes and lending standards which have been tightened in response to the housing boom of the past decade which resulted in millions of houses going into foreclosure. The pace of home sales is below the 5.1 million homes sold in 2013 and off the pace of 5.5 million annual sales that would be consistent with a healthy housing market. Sales of existing homes began to slow in the second half of 2013 as mortgage rates crept up from historic lows, but home prices continued to rise due to a lack of available homes for sale.