Updates from G4S, Pearson and Balfour Beatty

China's move to devalue its currency, lifting the price of its imports, sent shockwaves through the share prices of miners yesterday: Glencore and BHPBilliton were dragged 7.2% and 5% down (to 191p and 1148.50p); luxury firm Burberry was also hit, sinking more than 4.4% to 1536p. Bright spots? Prudential soared 4.6% to 1577p on better earnings, plus optimism on its Asian outlook.

The Chinese move - Beijing's biggest devaluation for two decades - shook the Dow Jones, down 1.2% to 17402.8, but the Big Board was also hit by the price of oil, slipping to a six-year low on news of an OPEC production hike.

Let's begin with a half yearly update from G4S. Underlying revenues climb to £3,285m from £3,196m while profits climb to £193m from £184m. Earnings per share rises from 5.6p to 6.1p. G4S' interim dividend climbs 5% to 3.59p per share.

Since January the outsourcer claims new work worth an annual contract value of over £680m has been won plus £2.2bn of new work in the bidding or negotiation stage that provides support for future sales, it claims.

Momentum through the first half should "deliver further improvements in the group's performance in the second half. We made good progress with our plans and there remains significant opportunity to realise the full potential of our strategy."

We move onto Pearson (which recently sold off the FT). Pearson says it's now getting rid of its 50% stake in The Economist Group with a £469m holding sold to Exor, owned by the Italian Agnelli family.

However the transaction is subject to a number of regulatory approvals plus approval by a 75% majority of Economist Group shareholders, as well as the group's independent trustees.

"Pearson," says chief exec John Fallon, "is now 100% focused on our global education strategy. The world of education is changing rapidly and we see great opportunity to grow our business through increasing access to high quality learning globally."

Lastly, Balfour Beatty. Underlying revenues remain stable at £4,085m (2014: £4,072m) the house builder claims but there's a total underlying loss in the first half of £135m (2014: profit £37m).

These numbers include a £152m shortfall, in line with indicated range of the July trading update, "reflecting historic issues in construction". However the news means that Balfour will scrap its dividend.

"We have," says chief exec Leo Quinn, "a new senior leadership team and an organisation re-aligned with key customer sectors. We are on course to meet our 24-month targets for £200m cash in and £100m cost out."

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