Here's your complete preview of this 4-day week's big market-moving events

From one holiday-shortened week to another.

The past week was mostly quiet, but highlighted by three straight up days and one flat day in the stock market. Read this, this, this, and this.

US markets will be open from Monday through Thursday, but will be closed Friday for New Year's Day.

As we count down the final trading days of the year, here's your Monday Scouting Report:

Top Stories

• Worrisome gaps. Accounting for earnings is a complicated business. In a recent note to clients, Bank of America Merrill Lynch's Savita Subramanian observed that reported earnings have exhibiting some unusual trends. From her note: "The proportion of companies beating on EPS (60%) was the highest since 3Q10, while the proportion missing on sales (59%) was the highest since 3Q12 - with the gap between the two surprise ratios the widest since 1Q09. Only Health Care and Tech saw both top and bottom line beats. While companies have been nimble about managing earnings to expectations, demand continues to weigh on sales… Another trend worth watching: since late last year, pro forma S&P 500 EPS has exceeded reported (GAAP) EPS by more than 30%, well above the ~10% gap for most of 2013 and 2014 and the widest gap since the Financial Crisis. In 3Q15, nearly 60% of the difference between GAAP and adjusted EPS was attributable to Energy, Metals & Mining and Machinery, where asset impairments/write-downs were the biggest contributors. Another ~20% of the difference was related to Health Care (chiefly Pharma, Biotech and Health Care Equip/Supplies), largely due to acquisition-related costs/impairments." For more context, read this.

Economic Calendar

• Dallas Fed Manufacturing (Mon): Economists estimate this regional manufacturing index deteriorated to -7.0 in December from -4.9 in November. Here's Wells Fargo's Sam Bullard: "As one would expect given the plunge in oil prices, the Dallas Fed manufacturing activity index has run in contractionary territory throughout 2015. Renewed weakness in oil prices in December likely kept the headline index below the expansion/contraction level for the twelfth straight month."
• S&P/Case-Shiller Home Price Index (Tues): Economists estimate home prices climbed 0.55% month-over-month in October or 5.60% year-over-year. Here's HSBC: "Home prices have been on an upward trend in most parts of the country since 2012. Over the past year, the Case- Shiller 20-city index has increased by 5.5%. "
• Consumer Confidence (Tues): Economists estimate the Conference Board's measure of sentiment jumped to 93.8 in December from 90.4 in November. Here's Wells Fargo's John Silvia: "Nonfarm payrolls in November posted a second consecutive strong reading, allaying some fears regarding the labor market. We expect consumer confidence will have bounced back in December on the back of more upbeat economic data. In addition, the renewed slide in gas prices will likely support confidence moving into the holiday season. That said, the volatility in financial markets will likely weigh on confidence, leading to only a modest gain."
• Pending Home Sales (Wed): Economists estimate pending sales climbed 0.6% month-over-month in November. Here's UBS's Sam Coffin: "The pending home sales index has probably stopped falling after a net decline over the past six months. We project a 1.0% increase in November after little change in October. Our forecast is backed by improving housing indicators, in particular rising mortgage applications."
• Initial Jobless Claims (Thurs): Economists estimate initial claims climbed to 273,000 from 267,000 a week ago. Here's Wells Fargo's Bullard: "Initial jobless claims continue to trend at a low level, reflecting firms' content over current staffing levels against today's moderate demand outlook. Given the holidays, weekly movements can be volatile with seasonal adjustment issues and therefore it is best to monitor the four­week moving average for underlying trends during this period."
• Chicago Purchasing Manager (Thurs): Economists estimate this index improved to 50.3 in December from 48.7 in November. Barclays: "We look for the Chicago PMI to rise to a neutral reading of 50 in December, up from 48.7 in November. This indicator of Chicago-area activity has been volatile throughout 2015, and last months' survey results were no exception as production, new orders and inventories all fell sharply. A bounce from these moves should bring the headline index higher at year-end."

Market Commentary

Since the financial crisis, S&P 500 companies have spent trillions of dollars buying back shares of their own stock. In the third quarter alone, these companies gobbled up $156 billion worth of themselves.

It's important to note that these buybacks - which are enormous enough to sway markets - don't occur evenly throughout the year.

"Typically, we have a huge tailwind in December from buyback action," JonesTrading's Dave Lutz observed on Thursday. "Fascinating: November/December has combined for almost 23% of annual buyback budgets from '07-'14(ex-'08)."

"This tailwind vanishes quickly, as January only has 3% of the total buyback allotments spent," Lutz noted.

If this pattern holds, we may witness a spike in volatility come January.