Unless you are psychic or trying to lose money, the simple answer is no. Timing market swings is a risky endeavor at best -- even for the most sophisticated investor. Many people prefer dollar cost averaging in a soundly diversified portfolio as a long-term way to help manage market swings. This involves a sustained investment program such as payroll deduction at work. Since these savings are invested at regular intervals over time, market swings tend to average out. The key is to stay invested. Staying invested and riding out the portfolio peaks and valleys has historically appeared to be a valid long-term strategy. However, past performance does not guarantee future results. The investment return and principal value of an investment will fluctuate so that an investor's unit, when withdrawn, may be worth more or less than the original cost.
Note that dollar-cost averaging does not assure a profit and does not protect against loss in declining markets. This type of plan involves continuous investment in securities regardless of fluctuating price levels and investors should consider their financial ability to continue their purchase in the future.