US home prices skyrocketed by 16.6% year over year and shot up 2.14% from April to May – the fastest month-over-month increase ever recorded by the S&P CoreLogic Case-Shiller US National Home Price NSA Index.

“A month ago, I described April’s performance as ‘truly extraordinary,’ and this month I find myself running out of superlatives,” said Craig Lazzara, managing director and global head of index investment strategy at S&P DJI. “The 16.6% gain is the highest reading in more than 30 years of S&P CoreLogic Case-Shiller data.”

This acceleration is also reflected in the 10- and 20-City Composites, up 16.4% and 17% year over year. The highest annual gains in May were in Phoenix (25.9%), San Diego (24.7%), and Seattle (23.4%). All 20 cities posted higher 12-month price increases in May than in the previous month.