Newport Beach is the most expensive housing market in the U.S. averaging $1.8 million per home, according to the most recent home listing report by Coldwell Banker. This standing is due in part to the area's home price appreciation over the majority of the past decade. According to the FNC Residential Price Index, home prices in the Los Angeles metropolitan statistical area (which includes Newport Beach) appreciated 3.8% since 2003, to an index of 191.78 as of July. This is the fourth largest gain in home prices in the nation. The Baltimore MSA experienced the greatest home price appreciation over the last seven years, up 7% to 222.97 on the FNC index, followed by Seattle (up 5.7% to 178.27), Washington, D.C. (up 4.5% to 181.92), Los Angeles, and Portland (up 3.8% to 148.84). Indices for the five MSAs with the greatest amount of home price appreciation have fluctuated over the one year ending in July, but are generally lower than 2009. Home prices around Baltimore range between $256,344 and $806,817, according to Coldwell. Seattle's MSA home prices range from $193,444 to $702,048 and home prices in Washington D.C. average $539,037. By contrast, Coldwell found the most affordable housing market in the U.S. to be Detroit, where home prices have steadily depreciated over the past year to an index of 77.28 (FNC) and an average price of $68,000. Write to Christine Ricciardi.