The 19-country eurozone's economy is kicking into a higher gear in the wake of falling oil prices.

A brace of economic reports Wednesday point to economic activity picking up momentum after a year of stagnation, particularly in the crucial area of consumer spending.

In one of the clearest signals, retail sales in the eurozone rose in January by a monthly rate of 1.1 percent. The figure, published by the Eurostat statistics agency, was the biggest increase since May 2013.

January's rise was way more than the 0.2 percent uptick predicted in the markets and took the annual rate up to 3.7 percent, the highest since August 2005.

Like most Western economies, consumer spending is one of the bedrocks of economic growth in the eurozone and the fact that it's growing strongly and consistently — up for four straight months for the first time since records began in 2000 — is a positive signal.

For years, consumer spending in the eurozone has been held back by a number of factors, including high unemployment in many countries, government budget austerity and a general feeling of economic uncertainty.

Now, despite recent concerns over Greece's future in the eurozone, consumers appear to be gaining confidence. Falling unemployment is helping to boost spending, as is the fall in fuel prices, which has contributed to a general decline in price levels.

A separate report found the eurozone economy grew in February at its fastest rate in seven months.

Markit, a financial information company, said its monthly composite purchasing managers' index — a broad gauge of economic activity — rose for the third month running to 53.3 points in February from 52.6 the previous month, with new orders doing particularly well.

Though down from an initial estimate of 53.5, the index is at its highest level since July, 2014. Anything above 50 indicates expansion. Markit says the February survey suggests the economy grew by a quarterly 0.3 percent in the first three months of the year, the same as it did in the fourth quarter of 2014.

And in what may be a positive signal for the future, Markit recorded expansions in economic activity across each of the 'big-four' eurozone economies — Germany, France, Italy and Spain — for the first time since April, 2014.

Chris Williamson, Markit's chief economist, said the most encouraging aspect of the survey was the signs of renewed growth in France, Europe's second-largest economy. France has been a laggard during the recovery with many economists blaming the government for not pursuing enough reforms.

"The outlook has brightened for all countries," he said.

Williamson said activity over the coming months should be helped by a combination of factors including diminishing concerns over a Greek exit from the euro, the weaker euro and "perhaps most importantly" the start of the European Central Bank's 1 trillion-euro ($1.12 trillion) or so bond-buying program.