The Digital Commerce Director of VPBankS Underlines the Most Important Factor in Riding the Market’s “Wave”

In your opinion, should investors try to time the market bottom?

Mr. Nguyen Viet Duc:

In my view, if investors are not using margin, there is no need to attempt to time the market. This has been proven throughout history.

According to a recent study, if investors tried to time the market bottom during the period of 1970 – 1996 (approximately 300 months), missing out on just the 12 best months would result in their investment returns being halved compared to simply holding stocks. Testing this hypothesis for the period of 1997 – 2024, staying out of the market during the 12 best months would leave investors with a mere 5% return, comparable to long-term bonds. On the other hand, if investors had simply bought and held, their return would be 9.3%.

Missing out on just the four best months would significantly underperform the market. Hence, very few people can succeed in timing the market.

Meanwhile, “timing the top” is far more crucial than “bottom-fishing.” According to the aforementioned study, if one could avoid the 30 worst months of the S&P 500, investment performance could be increased by 50%. However,


both timing the top and bottom are incredibly challenging.

Additionally, the study presented three investment scenarios: investing 100% in stocks, investing 80% in stocks and 20% in bonds, and investing 60% in stocks and 40% in bonds. The results indicated that the performance differences between these scenarios were not substantial, only about 1%. Therefore, investors should not spend excessive time attempting to predict market movements.

Market timing is only suitable for those using margin. Investors should maintain a stable allocation of 80% in stocks. In adverse situations, they can sell a portion but should still hold around 70% of their portfolio, as missing just a few rising sessions of the VN-Index could result in underperforming the market. Only allocate about 20-30% of the portfolio for timing the tops and bottoms.

If using margin, timing the tops and bottoms must be relatively accurate. For equity investments, focus on selecting the best-performing stocks in each phase instead of trying to time the market.

If not timing the market, how should investors select stocks?

Mr. Nguyen Viet Duc:

When the market is sideways, investors tend to favor timing the tops and bottoms: buying when the VN-Index drops to 1,200 points and selling when it reaches 1,300 points. This short-term approach relies on predicting each upward movement of the VN-Index and is suitable for margin trading. If using margin during a short-term uptrend, any profitable trade will result in a win.

However, for equity investments, just one or two incorrect predictions can lead to issues. Reflecting on my investment journey, although I have accurately timed the tops and bottoms on multiple occasions, only one or two mistakes significantly reduced my investment returns compared to the market. Therefore, investors should learn from investment funds about creating scenarios for the market.

Most large funds never maintain less than 80% allocation in stocks. These funds only time the tops and bottoms within a 20% allocation of their portfolio. Over the medium term, solid stocks will consistently grow.

Smaller funds typically have three allocation levels: 100%, 80%, and 30%. When the market is extremely unfavorable, these funds will sell aggressively, reducing their allocation to 30%. For most of the time, they will maintain a 100% allocation in stocks. If the market undergoes adjustments and fluctuations within an upward trend, the fund will hold around 80%.

In my opinion, if the market is still on an upward trajectory with minor corrections, investors should maintain a 70-80% allocation in stocks and only sell significantly when the uptrend ends to await opportunities to buy at lower prices.

For investors who still want to time the market, it is crucial to pay attention to trend reversal points or exhaustion points (sequence). Various formulas can be used to predict these sequence points, such as Elliott waves or candle-counting methods.

When a stock has declined significantly and cannot drop further, investors should buy. Conversely, when a stock has been rising for an extended period, leading to a scenario where further upside is limited, but a substantial decline is possible, investors should start taking profits.


Knowing when to take profits is the most critical aspect of investing with market trends.

How can investors identify strong stocks?

Mr. Nguyen Viet Duc:

According to Goldman Sachs statistics, different sectors will reflect the market’s cycles. For instance, Vietnam’s robust GDP growth in 2025 boosted stock market performance, while valuations remained low, below the average of the past 5-10 years.

In this case, investors could allocate capital to commodities, financials, and other sectors. When market valuations are high, investors may consider technology and luxury goods stocks, which benefit from high valuations and rapid growth.

From a technical analysis perspective, looking back at 2024, VTP maintained an upward trend throughout the year, but there were corrections of up to 27%. This was because VTP’s beta was very high, so when the market corrected by 10%, this stock could have dropped twice or thrice as much. Applying this concept to leading stocks of this year, such as VIC or GEX, corrections of 30% are normal, and these are the buying opportunities. This is the price to pay if investors want to own stocks that can triple or quadruple in value.

Alternatively, from a fundamental analysis perspective, investors can purchase stocks that the market has overlooked. By doing so, investors reduce the risk of significant losses. When the market rises, these stocks will eventually follow suit. Simultaneously, if there are positive catalysts, such as the Israel-Iran situation for energy stocks, investors can reap double benefits. In this case, investors should avoid taking profits too early.

According to Jim Rogers, the right-hand man of George Soros, to succeed, investors must first, buy low and sell high. As I have shared before, the risk of not owning low-priced stocks when the market surges is considerable. Therefore, when you see stocks declining, you need to buy.

Secondly, investors should only invest in what they know and understand well. This is also emphasized by Warren Buffett.

Thirdly, investors need to comprehend economic cycles and industries. Only macroeconomic factors can cause market crashes, while geopolitical conflicts will not influence long-term trends.

Fourthly, be a contrarian and avoid following the crowd. If you want to avoid situations where you are fully margined and the stock price drops, focus on newly rising stocks, those accumulating, and only a small catalyst can trigger a 15-20% increase.

Fifthly, in emerging markets, investors must be cautious about exchange rate factors. Exchange rates influence growth and inflation, and as long as the rates are not unfavorable, the market will remain stable. For example, the recent stories of South Korean and Taiwanese stocks are related to exchange rates. In Vietnam, the sharp corrections in 2010-2012 and 2024 were also due to exchange rate issues.

Sixth, investors should be patient and disciplined.

Finally, investors need to prepare for market extremes. Markets often overbuy or oversell, so once you own a stock, you must be patient and disciplined enough to hold it until the valuation exceeds its true value.

Which sectors are you currently focusing on?

Mr. Nguyen Viet Duc:

Firstly, investors should pay attention to bank stocks, as they account for 50% of the total market capitalization. Within this sector, there are always winners, whether the market is up or down. Funds in Vietnam typically allocate 40-50% of their portfolios to bank stocks.

In the first half of this year, bank credit growth has been positive. Currently, banks are benefiting from economic growth and reduced risks.

For the energy sector, the current uptrend is still largely based on expectations rather than reality. However, if oil prices remain in the $70-80/barrel range for the entire year, these companies’ performance will improve.

Additionally, the retail sector deserves attention. Recently, the government has taken strong action against counterfeit and pirated goods. In the past few years, companies like DGW and MWG have been significantly impacted by these issues. Therefore, despite their strong performance, if there is a correction, investors can still consider buying.