When the fiscal year ends on September 30, the US Congress needs to approve 12 bills that fund the government or a temporary measure that extends the current funding. Otherwise, the government will run out of money and have to stop some or all of its non-essential operations. This is called a government shutdown, and it can happen if Congress and the president disagree on the budget or if the president rejects the funding bills. A government shutdown can affect many aspects of the society, such as the economy, public services, federal workers, and national security.
Investors are reacting to a possible government shutdown with a mix of caution and optimism, as it anticipates a temporary and limited impact on the economy and markets. However, investors are also closely watching the developments and negotiations in Congress and the White House, as any prolonged or unexpected outcome could change the sentiment and outlook.