PARIS — The eurozone economy expanded for a 22nd consecutive month in April, a private sector report showed on Thursday, but the modest pace of growth disappointed some analysts looking for more vigor resulting from the European Central Bank’s bond-buying program.

Purchasing managers across the 19-member euro currency zone reported growth in services and manufacturing, according to a survey conducted by Markit Economics, a data analysis firm. Markit said its composite output index slipped to 53.5 in April from 54.0 in March. A reading below 50 indicates contraction, while a number above that level suggests expansion.

The market consensus had been for a small increase in the index. The lackluster report might reflect concerns about the economic crisis in Greece, though the figure was still close to an 11-month high, said Jessica Hinds, an economist in London with Capital Economics. She added that the April index level appeared consistent with quarterly economic growth of about 0.4 percent, or about 1.6 percent on an annualized basis.

Markit said the survey showed growth beyond France and Germany, the region’s two biggest economies, at the fastest pace since August 2007. The data showed Germany slowing slightly from what remains a relatively good pace and France still just above stagnation levels.