Return the percentage change of daily stock prices

-- Return the percentage change of daily stock prices compared to the first stock price of the month for each stock.

    stock_id INT,
    stock_name VARCHAR(50),
    stock_price DECIMAL(10, 2),
    trade_date DATE
);


INSERT INTO DailyStockPrices (stock_id, stock_name, stock_price, trade_date) VALUES
(1, 'Stock A', 100, '2024-01-01'),
(1, 'Stock A', 105, '2024-01-02'),
(1, 'Stock A', 110, '2024-01-03'),
(2, 'Stock B', 200, '2024-01-01'),
(2, 'Stock B', 190, '2024-01-02'),
(2, 'Stock B', 195, '2024-01-03');


SELECT 
    stock_id,
    stock_name,
    trade_date,
    stock_price,
    ROUND(((stock_price / first_month_price) - 1) * 100, 2) AS percent_change
FROM (
    SELECT 
        stock_id,
        stock_name,
        trade_date,
        stock_price,
        FIRST_VALUE(stock_price) OVER (
            PARTITION BY stock_id, EXTRACT(YEAR_MONTH FROM trade_date)
            ORDER BY trade_date
        ) AS first_month_price
    FROM DailyStockPrices
) AS stock_data
ORDER BY stock_id, trade_date;