Turner & Townsend conduct a yearly survey of 43 construction locations on every continent.30 In 2017, the five most expensive cities in the world in which to build were, on a simple US$ comparison, and in order of expense: New York, San Francisco, Zurich, Hong Kong and London. When a measure like PPP is used, which factors living costs with prices, London tops the bill and New York slips to twenty-first, though the differences do flatten out. For New York, the market issue is huge, and thus a factor of productivity, as other places in Britain have roughly the same PPP value as New York. Building prices inflated on average by 3.5 per cent, 2.7 per cent in advanced economies, and here building costs generally increase more than inflation. The highest five building price inflations vary by 6–20 per cent. The five lowest vary by 0–0.5 per cent. Globally, there is a growth in markets but China is declining from a high 6.5–6%, the USA is growing (1.5–2.0 per cent) and the Eurozone is shrinking slightly (2–1.5 per cent). Preliminaries range from 5–15 per cent of construction costs but tend to be highest in the big cities and advanced economies where labour is expensive. Further away from cities there is less demand and margins thus tend to be 3–12 per cent lower than in inner cities. The highest margins are for rapidly growing cities (e.g. Johannesburg and Buenos Aires).