BHP Billiton said on Wednesday that its latest half-year results deviated from previous performances, achieving only a net income of $9.9 billion for the last six months leading to the end of December 2011.

The slide represented a clip of 5.5 percent, with the numbers falling short of market's expectation of at least $10 billion for the first half.

In a statement, the world's biggest mining firm attributed the slight profit decline to decreased output due to heavy rains that hampered production activities, which were complicated by minor labour unrests on its copper division.

Global financial woes, specifically in Europe, also contributed to the profit slide as demands for commodities dwindled that led to softening prices for a number of products being shipped by BHP, the company reported.

The latest results came out on the heel of BHP's record results in the same period in 2010 when the miner netted $10.5 billion, en route to an annual income spurt of 86 percent to $23.6 billion by the end of June 2011.

BHP, however, argued that last financial year's better results were largely supported by consistent surges in iron ore and copper prices, two products that perennially power the company to unprecedented profitability.

The company admitted that overall production suffered major hits in the period spanning from July to December, its effects sustained in shipments that were made until the final months of 2011.

Production, however, recovered in the last six months of the same year, paving the way for higher expectations in the second half of financial year 2011-2011, BHP said.

BHP revealed that iron ore and natural gas outputs exceeded its own expectations in the period, bolstering the company's projections that profit guidance would be met by the end of June 2012.

"We expect underlying demand growth rates to remain robust, so long as the macro-economic policy setting of the developing world retains a growth bias," BHP said on its statement.

Worries, however, remain in place as economic indicators, with manufacturing and construction still hobbled by challenges, suggest that the current year will be marked by conflicting shares of surges and difficulties.

Economists have predicted of a possible global downturn to come out from the ongoing debt crisis in Europe that has already battered key economies in the region, with the latest setbacks highlighted by wholesale credit downgrades absorbed by many countries within the continent.

Slowdowns are also expected to hit China, India and South Korea this year, stressing further of weakening market situations around the world.

However, BHP said that Japan and the United States have shown signs of turnaround this year, which the company said will be likely sustained for the rest of the year, giving the company enough hope that its overall market will remain profitable.