The summer housing market is heating up.

According to data from the National Association of REALTORS®, the Pending Home Sales Index smashed analyst expectations, jumping 8 percent on a monthly basis in May. 

Wall Street calls were for an increase of just 0.5 percent. 

It was a surprise result that, coupled with the recent stronger-than-expected New Home Sales and Existing Home Sales readings, has sparked housing market optimism in TN and nationwide.

The biggest reason for the optimism is because of what the Pending Home Sales Index measures. 

In contrast to "traditional" housing data which reports on how housing performed two months ago, for example, the Pending Home Sales Index is a forward-looking indicator; a predictor of future market activity based on freshly-written contracts between buyers and sellers.

In other words, the Pending Home Sales Index looks ahead -- not back. This is reflected in its methodology which states that 80% of homes under contract close within 2 months, and a large percentage of the rest close within Months 3 and 4.

Because May's Pending Home Sales Index rose sharply, therefore, we can expect similar jumps in the Existing Home Sales figures of June and July.

For housing and home prices, this is a positive but the gains won't apply to each home equally. The Pending Home Sales Index is still a national report for a market built on local sales. What's happening on your particular street in your particular neighborhood may not reflect what's happening somewhere else.

For accurate, real-time data in your local market, ask a real estate agent for statistics.