Business units at Macquarie Group will have to meet return on equity targets, and those that don't will be "on the way out", management said on Friday.That's the rhetoric, at least, though the group's board will take a long term view of the ROE prospects of "markets-facing" businesses that are making no profit at the moment but may once again earn high returns.The group reported a net profit of A$305 million for the half year to September 2011, down by 45 per cent on profits six months ago. The return on equity for the half year was 5.7 per cent annualised, down from 10 per cent six months ago and seven per cent a year ago.One response to these poor returns is a planned buyback up of to 10 per cent of shares, though the timing of this is vague (and explained in the next article). One innovation in the disclosure of keen interest to the investment analysts asking questions at Friday's briefing was a discussion of the capital employed and returns on equity in Macquarie's six main business units. Three are profitable, earning returns in excess of 20 per cent, while three are not and more or less just broke even in the half year to September 2011.As the table shows, Macquarie's managing director, Nicholas Moore, regards profitable divisions as "annuity-style" businesses, though two of these are rather traditional banking businesses, albeit serving niche customers, such as fleet managers, airline operators and Canadian home-buyers. Those earning no profits at present are mostly traditional investment banking businesses, though one - Fixed Income, Currencies & Commodities - is not.While some businesses are being sold or scaled down (such as Private Wealth in Asia) the markets-facing businesses are being given plenty of latitude.Other business units are also under scrutiny and may be sold. Moore later named Macquarie's 22 per cent stake in Sydney Airport owner MAp, as one sale prospect, the Australian Financial Review reported.Greg Ward, Macquarie's chief financial officer, said: "We are looking at the return on equity that we think... [these businesses] can be providing for us going forward it, and, if they don't meet the requirement, they are basically on the way out."Moore told the briefing that returns in the order of 40 per cent, for Macquarie Securities, for instance, are "the sort of return we expect to receive, [which] these businesses have provided in the past."Securities continues to be a good business, when the market goes, but obviously there is a degree of market volatility."Our FICC business has continued to be strong with the exception of the last six months throughout the period."For the three market-facing businesses, the key element there is market conditions.  We think we are very well placed for market conditions after a comeback there."One detail of the September-half result that may surprise critics is the extent of cost cuts. Macquarie said it cut operating costs by 12 per cent, to $2.8 billion over the half, a result achieved by process improvements (such as amalgamating