A more thorough explanation:

The Jobs and Growth Tax Relief Reconciliation Act of 2003 (JGTRRA) was a law passed by President George W. Bush to help the economy grow after a recession in 2001. The law aimed to encourage people to invest more money by reducing taxes.

One of the most important parts of the law was that it lowered the tax rate on long-term capital gains from 20% to 15%. This meant that people who made money from selling stocks or other investments they had held for a long time paid less in taxes. The law also made the tax rate on stock dividends the same as the rate on long-term capital gains. Additionally, the law increased the amount of money that people could earn before they had to pay the alternative minimum tax.

Some people believe that the JGTRRA and another law passed in 2001, called the Economic Growth and Tax Relief Reconciliation Act (EGTRRA), helped the economy grow after 2003. However, others think that these laws encouraged people to invest too much money, which led to a recession in 2008.

For example, imagine that you bought some stock in a company for $100. You held onto the stock for several years, and it grew in value to $150. If you sold the stock before the JGTRRA was passed, you would have had to pay a 20% tax on the $50 profit you made. That means you would have paid $10 in taxes and kept $40. However, after the JGTRRA was passed, you would only have to pay a 15% tax on the $50 profit. That means you would only have to pay $7.50 in taxes and would keep $42.50. This might encourage you to invest more money in the stock market, which could help the economy grow.