Frankfurt — One of the biggest money-printing programs of all time, a geyser of cash that may have prevented the collapse of the eurozone, will officially end in a few weeks in a slow-motion wrap-up that reflects lingering risks to the region.

The European Central Bank said on Thursday that at the end of December it would stop adding to its stock of government and corporate bonds, the so-called quantitative easing program it has used to hold down interest rates and encourage lending.

After a decade marked by recessions, financial crises and political turmoil that nearly tore the eurozone apart, the wind-down of the bond-buying program showed that the central bank was confident enough in the eurozone’s health to begin taking the region off life support. It was also a vindication of sorts.

Although not a surprise, the end to the stimulus program — or more precisely, the end of its expansion — was a milestone for the euro a few weeks before the currency marks its 20th birthday.