Today I’m discussing the share price outlook of two FTSE 100 frighteners.

The steady share decline of outsourcing specialist Capita Group (LSE: CPI) shows no signs of slowing, the stock hitting fresh 10-year lows just this week. Capita has now shed 56% of its value since the bells rang-in New Year’s Day.

And I believe there could be even more blood on the floor, starting with Capita’s next trading update scheduled for 8 December.

Capita warned in September that it had been hit by “a slowdown in specific trading businesses, one-off costs incurred on the Transport for London congestion charging contract and continued delays in client decision making.” This forced the business to scale back its 2016 profit projections. Underlying pre-tax profit is now expected at between £535m and £555m.

And the landscape hasn’t exactly improved since then going by recent trading updates from Capita’s outsourcing peers. Mitie reduced its own profit forecasts for the second time in as many months in November after warning of “changing market conditions as clients adjust to rising labour costs and economic uncertainty.”

Both outsourcers have announced heavy restructuring in light of these pressures, with Capita announcing last month its reorganisation into six divisions with each to be led by a new executive. The firm said these measures will provide “greater management strength and depth across all of Capita’s operations,” as well as “a deeper sales and business development focus and greater support in driving organic growth.”

But these measures are likely to prove a mere sticking plaster should the uncertainty surrounding the Brexit vote continue to hamper investment decisions by its clients in 2017 and beyond.

The City expects Capita to bounce from a 7% earnings decline in 2016 with a 3% rise next year, but this  rebound is built on extremely shaky foundations, in my opinion. So although it trades on a P/E ratio of just 7.8 times for 2017, I reckon Capita’s share price is in danger of shuttling still lower.

Iron giant

I reckon recent share price strength at BHP Billiton (LSE: BLT) leaves it in danger of a sharp share price reversal too.

The diversified mining giant saw its share price rise 7% during November, meaning BHP Billiton has soared by almost three-quarters since the start of 2016. But to me, this upward surge has little basis in reality.

The rise of BHP Billiton and its peers has been built on a crazy advance in iron ore values. The steelmaking ingredient has almost doubled in price since the beginning of the year and came within a whisker of the $80 per tonne marker recently.

But prices have ducked lower in recent days as Chinese exchanges hiked their trading fees and margin requirements to cool speculative buying. Meanwhile, supply and demand indicators remain a concern with China embarking on massive cuts to steelmaking activity, and the country’s ports already swamped with excess material.

The commodities glutton is going to need to continue hoovering up vast swathes of iron ore to offset the production ramp-ups pursued by BHP Billiton and its peers. However, this could prove an extremely hard task should global trade flows continue to cool.

Given this backcloth, I reckon BHP Billiton is in danger of toppling, particularly as the firm currently deals on a heady forward P/E rating of 18.6 times, so investors should give the business a wide berth.

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Royston Wild has no position in any shares mentioned. The Motley Fool UK has no position in any of the shares mentioned. We Fools don't all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors.