Editor's Note: "Retirement Savings on Track? How Much You Should Have by 50 and 55" is part of an ongoing series on getting your retirement on track by age. The second story is "Retirement on Track?

DeepSeek's AI model is cheaper due to its selective activation of model parts. The company, backed solely by High-Flyer, has no immediate IPO plans. Invest in AI trends through Nvidia, Microsoft, or ...