Below is a simple HTML and JavaScript code for a financial calculator.
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Stock Market Basics Calculator
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This is a simple calculator for calculating the final amount of investment in the stock market. The user inputs the initial investment amount, the annual interest rate, and the number of years of investment. The final amount is calculated using the formula for compound interest.
Note: This is a very basic calculator and does not consider many factors that can affect the final amount of investment in the stock market. Please use it as a starting point and modify it according to your needs.