S&P 500 hits new highs, flight cancellations, the restaurant industry's value push and more in Morning Squawk

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Here are five key things investors need to know to start the trading day:

Joy to the investor! While some market participants worried that the so-called Santa Claus rally wouldn’t materialize this year, the major indexes all notched wins in last week’s holiday-shortened trading period. The S&P 500

also gave traders the gift of new all-time highs.

Here’s what to know: