By Nick Godt

A huge three-week rally in stocks will meet a number of stumbling blocks next week, including some earnings, a meeting of finance ministers and central bankers from the G20, as well as the key jobs report for March.

Congress will also be hearing comments on key proposals to change to mark-to-market accounting.

"We've had the largest three-week move in stocks since 1938," said Hugh Johnson, chairman of Johnson Illington Advisors. "It's probably asking for a lot that the market continue to move higher over the next three weeks. We have some formidable challenges coming up ahead, and it would seem that it's time for a breather."

On Friday, stocks fell but still closed a strong week of gains. The Dow Jones Industrial Average fell 148 points, or 1.9%, to end at 7,776. The S&P 500 Index fell 16 points, or 2%, to end at 815, while the Nasdaq Composite Index (RIXF) lost 41 points, or 2.6%, to end at 1,545.

For the week, the Dow rallied 6.8%, the S&P 500 gained 6.2% and the Nasdaq rose 6%. For the month so far, the Dow is up 10.1%, the S&P is up 11% and the Nasdaq adds 12.2%.

The S&P 500, which investing professionals use as the benchmark of the broad market, scored its best 14-day gains since July 1938.

But some of the stock market's reactions on Friday led some to believe that the rally might be long in the tooth ahead of the first-quarter earnings reporting season.

"Back in February and early March, we had a number of banks coming out with upbeat quarterly results and forecasts, and that helped spark the rally," said Owen Fitzpatrick, head of U.S. equities at Deutsche Bank.

"But even if it got a bit better in March, overall industrial activity has remained weak and that will translate into weak earnings and companies taking down their forecasts," he added. "This will throw a little bit of cold water on this rally."

For instance, Accenture Ltd. (ACN), the consulting and outsourcing firm, warned about its outlook for the rest of the year on Thursday.

Of particular interest next week will be quarterly results from BlackBerry maker Research In Motion Ltd. (RIMM) on Thursday after the close. That same day will also bring results from Micron Technology Inc. (MU), Monsanto Co. (MON) and Rite Aid Corp. (RAD)

On the brighter side for financials stocks, Fitzpatrick pointed out, Congress will hear comments on proposals for banks to suspend mark-to-market accounting, which would allow them to stop writing off all their toxic assets.

Economy

Data will come in play next week after some signs of improvement in the housing market raised hope for the economy. Key will be the S&P/Case Shiller index of home prices for January, due out Tuesday, followed by the Chicago manufacturing and consumer-confidence surveys for March.

Wednesday will bring the national manufacturing survey for March from the Institute of Supply Management, along with pending home sales and a private-sector survey of employment.

Friday will bring the ISM's service-sector survey and the all-important March employment report.

G20

Finance ministers and central bankers from the G20, which includes 19 of the world's largest economies and the European Union, are due to meet April 2 to address ways to tackle the global financial and economic crisis.

While not officially on the agenda, some underlying tensions about trade and currencies might come to the fore. The governor of China's central bank on Monday called for a new global reserve currency to replace the dollar.

"There are hurdles," said Johnson of Johnson Illington Advisors, "not just with the economic numbers and earnings reports next week, but also with the rhetoric on currencies. There are tensions starting to build over some underlying trade issues."

Tensions over currency and trade were a fixture of U.S.-Chinese relations over the past few years. The United States, along with other countries, has accused Beijing of keeping the yuan artificially low to boost its exports.

Meanwhile, China, the largest buyer of U.S. Treasury bonds, also expressed concern earlier this month about the safety of its investments. The massive amounts of U.S. debt issued have pressured bond prices and also threatened the strength of the dollar, which could further reduce the value of holding Treasurys.

Now, the Federal Reserve is actively buying Treasury as part of its $300 billion program announced last week, to further bring down borrowing costs and boost the economy.