Sales of newly built U.S. single-family homes unexpectedly tumbled 3.6 percent in September in their first drop since March, but the inventory of new homes available at the end of the month shrank to the smallest in 27 years, government data showed on Wednesday.

September single-family home sales totaled 402,000 units at an annual pace. Analysts polled by Reuters had expected new home sales to rise to a 440,000 unit annual pace from a revised 417,000 units in August, which was originally reported as 429,000 units.

The median sales price rose in September to $204,800 from $199,900, while the average sales price rose to $282,600 from $256,500.

(Reporting by Lisa Lambert, Editing by Chizu Nomiyama)