Every December, a strange phenomenon often occurs in the financial market: investors suddenly become extremely active - eager to close losing positions, pursue popular sectors, and adjust annual income performance. This behavior seems rational, but in fact it is deeply driven by the year-end mental accounting reset (Year-End Mental Accounting Reset). Wmax behavioral finance series points out: the real risk lies not in market fluctuations, but in our excessive meaning given to "time nodes".

Annual Cut of Mental Accounting

The "mental accounting" theory proposed by Nobel Prize winner Richard Thaler points out that people divide funds into different "accounts" based on source, use or time, and assign different risk preferences. The end of the year is the time when mental accounts are forced to "close".

Many traders will unconsciously separate "this year's losses" from "next year's opportunities". For example: "This loss cannot be carried over to next year, otherwise it will affect the New Year's mentality"; or "The principal must be earned before the end of the year to be considered complete." This slicing ignores the homogeneity of funds—no matter when you lose money, the impact of a $1 loss on your overall wealth is the same. However, the brain has a false sense of restart due to the "calendar page turning", which leads to hasty closing of positions or risky additions to positions.

The amplification of the disposal effect at the end of the year

The "Disposition Effect" refers to the tendency of investors to sell profitable positions too early but hold on to losing positions for a long period of time. This deviation was significantly amplified at the end of the year and evolved into forced disposal behavior.

Research shows (Odean, 1998) that investors are 23% more likely to close losing positions in December than in other months. On the surface it is "stop loss discipline", but in fact it is to "clear bad records". What is even more dangerous is that some people will operate in the opposite direction - chasing hot assets higher in the last few trading days in an attempt to "beautify the annual statement." This behavior is not based on new information but on obedience to the psychosocial ritual of “annual review.”

Social comparison pressure: Who is showing off their “annual earnings”?

At the end of the year, social media was flooded with content such as “My 2025 Profit Curve” and “XX Strategy Annualized at 50%”, triggering strong social comparison. When you see others showing profits, the brain's reward circuitry is activated, and anxiety is produced in the anterior cingulate gyrus - even if you had no original intention to compare.

This pressure can distort risk perception:

Profiters may stop profits prematurely because they are "fearful of taking losses"; losers may increase leverage because they are "unwilling to lag behind"; bystanders may blindly follow the trend due to FOMO (fear of missing out). Behavioral experiments show that in a simulated year-end environment, the probability of subjects taking high-risk positions is 37% higher than usual, and the regret rate afterward increases significantly. The “year-end show” in the digital age is becoming a new breeding ground for irrational decision-making.

How to resist the psychological trap at the end of the year?

The first way to do this is to break out of the “annual” narrative frame. Ask yourself:

"If today was June 30, would I still make this decision?"

If the answer is no, it means that the decision-making is interfered by time nodes rather than driven by real logic.

Secondly, establish a multi-year position evaluation mechanism. Classify positions according to "whether the opening logic is still valid" rather than "whether it is profitable". For example: the survival of a semiconductor position purchased due to the demand for AI computing power should depend on whether the industry trend continues, rather than whether the capital can be recovered before December 31.

Finally, proactively block “annual summary” content. At the end of the year, reduce browsing revenue lists, rankings, annual reviews and other information sources to avoid emotions being swayed by group narratives. True investment discipline is sticking to the rules when no one is looking.

Conclusion: Time is just a scale, not a referee

Turning the page on the calendar does not change market patterns, nor does it reset your risk tolerance. Those hasty decisions made due to the "New Year's Eve" often become the first lessons of the new year. Wmax behavioral finance series reminds: Don’t let the ritual sense of time obscure the essence of decision-making. True professionalism is to still be able to hear your own voice of reason in the noisy year-end atmosphere.