If the annualized rate of return of 8% is fixed, it can be regarded as a monthly deposit in 500 yuan for four years.

The interest calculation formula of lump-sum deposit and withdrawal is: interest = monthly deposit amount × monthly product × monthly interest rate.

Cumulative monthly product = (deposit times+1) * (deposit times)/2 = (48+1) * 48/2 =1/76; Monthly interest rate = 8%/12; Monthly deposit =500.

After four years, the interest income is 500 *1176 * 8%/12 = 3,920 yuan, and the four-year investment principal is 500 *12 * 4 = 24,000 yuan. The total principal and interest is 27,920 yuan.

Automatic investment plan

Generally speaking, there are two ways of fund investment, single investment and regular quota. Because of the low starting point and simple method, the fund is also called "small investment plan" or "lazy financial management"

"Compared with fixed investment, the one-time investment income may be high, but the risk is also great. Because it avoids the influence of investors' subjective judgment on the timing of entry, the risk of fixed investment is significantly lower than that of stock investment or single fund investment.

The fixed investment of the fund is similar to long-term savings, which can spread the investment cost evenly and reduce the overall risk. It has the function of automatic bargain-hunting plus code and bargain-hunting minus code. No matter how the market price changes, it can always get a lower average cost.

Therefore, regular fixed investment can smooth the peaks and valleys of fund net value and eliminate market fluctuations. As long as the selected funds grow as a whole, investors will get relatively average returns without worrying about the timing of entering the market.