Editor's Note: Jon D. Markman writes a weekly column for CNBC on MSN Money that is republished here on TheStreet.com. Amid the hoopla over the six-year high in the Dow Jones Industrials, it's easy to neglect three more important milestones facing investors today: the transition of the economy from fast to slow, the switch from an expectation of interest rate increases to rate cuts, and the handover of market leadership from small stocks to large. As these transitions gain traction, investors need to develop a new strategy for building wealth via the markets or face a lot of heartache. Before I explain -- and give you a list of 25 stocks well-suited to this environment later in this column -- let's review how we got here. For the past three years, the U.S. economy has run at close to full speed, sort of like a car barreling down an interstate. That kind of behavior leads businesses to burn up a lot of raw materials and hire employees, driving up prices and wages. You might think that federal authorities would love that, but they don't. Higher prices and wages, also known as inflation, are Public Enemy No. 1 to investors worldwide who keep our country in business by buying U.S. government-issued bonds. The most important job of U.S. central bankers, the folks who run the Federal Reserve, is to keep prices stable. The Fed tapped the brakes on our runaway economy by raising interest rates for 17 months in a row through July. Higher rates make it harder for companies and individuals to borrow money, slowing down business expansion and consumer purchases.