The spring homebuying season continues its brush with optimism with median list prices of homes for sale nationwide up 5.56 percent over the last year, according to Realtor.com data updated through March 2012. The jump to $189,900 brings the national median list price close to what it was two years ago.

Continuing a distressed-market turnaround trend, the Phoenix-Mesa, Ariz., metro took the No. 1 position on the list with a 23.5 percent jump from a year ago, to $179,000. The Miami metro made No. 2 on the list with a 22.27 percent list-price increase from a year ago, to $269,000. Both Phoenix and Miami were among the top 10 metros for year-over-year reductions in for-sale inventory, ranking No. 3 and No. 5, respectively.

Editor’s note: Data from Realtor.com’s first-quarter real estate trend data report. The report analyzes data for 146 U.S. metros and includes single-family homes, condos, townhomes and co-ops.

Florida showed especially strong in median list-price growth in the last year, with five of the top 10 metros located in the Sunshine State. In addition to Miami, Punta Gorda made the list at No. 4 (17.5 percent), along with Daytona Beach (No. 8 at 15.47 percent), West Palm Beach-Boca Raton (No. 9 at 15.38 percent) and Naples (No. 10 at 15.38 percent).

Although they didn’t make the top 10 list, strong growth in median list prices in other Realtor.com-tracked Florida and Arizona metros like Fort Myers-Cape Coral (up 15.31 percent), the West-Ariz. rural statistical area (up 13.64 percent) and Fort Lauderdale (up 8.39 percent) suggest a bottom has formed in these hard-hit housing markets.

However, Realtor.com analysts noted that the large shadow inventory of potential foreclosures in these states could undermine this optimism and keep prices low as supply floods the market.

The Phoenix metro area has had a particularly notable shift in fortunes. In March 2011, it was No. 4 in the top 10 metros Realtor.com tracks for year-over-year median list-price declines. The median list price was down 14.2 percent from March 2010. List prices are a leading indicator, and may reflect optimism about a market that doesn’t always translate into actual sale prices.

The current median existing-home price in the Phoenix metro area is $124,500, less than half of the metro’s peak list price of $267,000, seen in the summer of 2006 at the height of the housing boom.