Updates from Halfords, Ashtead Group and Diploma

More gloom for the FTSE 100 on Tuesday: the index slumped more than 3%, or 190 points, to 6,058.5. Only one riser - Meggitt, up 2.3% to 488.7p. Miners tumbled fast on Chinese unease: Glencore and AngloAmerican plunged 10% and 7.7% (to 133.50p and 684.40p respectively); BHPBilliton was down 6.7% to 1056p. There were steep falls too for 3iGroup and OldMutual.

Stateside things were equally rough, more or less, with a 2.8% fall in the Dow to 16,058.3. ExxonMobil slumped 4.2% while Microsoft was down 4.1% not helped by unpromising data from Chinese manufacturing. Over in Japan the Nikkei was also down hard.

We nip into Halfords to start the morning. The air is definitely out of cycling sales: like-for-like is down 1.3% in the 8 weeks to 28 August. That's peak-time for cycling sales. Poor weather, up to a point, is blamed.

For the first half, Halfords says it anticipates retail gross margin to be at the better end of previous full year guidance range (-25 to -75 basis points year-on-year decline) with Retail operating cost growth of around 3%.

Halfords adds that "through mix benefits in margin and prudent cost control in line with the first half, management anticipates full year Group profit before tax...broadly in line with prevailing market consensus".

Next, an update from equipment rental operator AshteadGroup. Group rental revenue is up 20% to £539.6m with Q1 pre-tax profit of £161m, up 23% at constant exchange rates.

Group revenue overall increased 35% to £619m in the quarter (2014: £458m) with strong growth in both of its business arms. Some of the growth appears to be riding on a more robust US construction market.

"With both divisions performing well," said the company, "strong end markets and our strategy clearly working, we expect full year results to be in line with our expectations and the Board looks forward to the medium term with confidence."

Finally, technical products company Diploma. Reported revenues for the year to 30 September are expected to increase 9% due to acquisitions contributing 10% to Group revenues.

Diploma says this is offset by a reduction of around 2% in revenues from currency volatility. Headwinds to organic growth have continued and in certain cases strengthened through the second half of the year it adds.

Currency volatility "will impact next year's operating margins in the Group's Healthcare businesses as existing currency hedging contracts expire and are replaced by more expensive contracts".

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