We've began tracking existing home sales over the last several months, using Zillow's seasonally adjusted price and sales volume data to estimate the total aggregate valuation of these sales at the regional and state level in order to get a sense of the relative health of the real estate markets in these geographies.
Many of these markets have shown signs of having peaked in or around March 2018 for this equivalent measure of market capitalization, but thirteen states have, within the first quarter of 2019, seen their real estate markets for existing homes reach new highs. The following chart reveals the 13 states whose real estate markets have been the strongest in 2019, showing the trends for aggregate existing home sales in each from January 2016 through the latest data available for each in either February or March 2019.
Perhaps the most remarkable of these states is Washington, which had seen the market cap for its existing homes fall by 16% from a peak in March 2018 through October 2018, which has since rebounded strongly to reach a new peaks in February and March 2019, which we believe is attributable to a rapid decline in U.S. mortgage interest rates, which has made the high prices of the state's existing homes more affordable in recent months. Other states have shown a similar pattern to Washington over this period of time, including New York, Virginia, Massachusetts, and Ohio.
Other states have shown less volatility as the aggregate value of their existing home sales have grown to new heights, including Arizona, Michigan, Tennessee, Indiana, Alabama, Nebraska, Delaware, and Alaska.
The following charts shows our estimates of the peaks in the aggregate value of existing home sales in these thirteen states, and indicates the month in the first quarter of 2019 when it reached those record value.
These estimates are based on preliminary data, where Zillow's data is subject to revision as their sources update and report more complete information.