Sobre Números-Índices podemos dizer que:

Item 4: Um índice de preços é formado pelos produtos A e B. Se o preço do produto A aumenta 312 %, o preço do produto B permanece inalterado e o índice de preço sobe 5,8 %, então a ponderação em percentual do produto A no computo deste índice é 18,6 %.

Some countries look more prone to rising inflation than others. From an analysis of wages, inflation expectations, demand and capacity pressures, and monetary growth, Mr Cates infers that Argentina, Brazil, India, Russia and the Middle East oil exporters face the biggest risks in the months ahead. Pressures seem less great in China, Mexico, South Korea and Turkey.

Clearly, monetary policy needs to be tightened. Instead, it has in effect been loosened: real interest rates are generally lower than they were a year ago. Short-term interest rates are also unusually low relative to nominal GDP growth a crude gauge of where rates should be, which implies that monetary policy is very loose (...). The broad money supply has grown by an average of 20% over the past year in emerging economies, almost three times the pace in the developed world (…). Russia's money supply has swelled by fully 42%.

Add all this up, and emerging economies bear strong similarities to rich countries in the 1970s, when the Great Inflation took off. A synchronised boom in the world economy has caused commodity prices to surge. Governments have responded with subsidies and wage and price controls. Official statistics understate price pressures. Economies are running at full pelt. Money-supply growth is soaring. Inflation expectations are not anchored and labour markets are fairly rigid, increasing the risk of a spiral in wages and prices.

According to conventional wisdom, the monetary-policy mistakes that caused the Great Inflation are much less likely today because central banks are independent of politicians. But unlike the Federal Reserve and the European Central Bank ECB, many central banks in emerging economies notably China, India and Russia are not fully independent. In another echo of the 1970s, they often face intense political pressure to hold rates low to boost growth and jobs.

The text remarks on:

Item 4: the absence of price controls.

With capital so mobile and America's monetary policy so loose, emerging economies have no easy fix for inflation. Interest rates clearly need to be raised by a lot, but a tidal wave of capital could either boost domestic liquidity or cause currencies to become overvalued. Brazil has allowed its currency to rise by more than 100% against the dollar over the past five years. This has helped to bring inflation down (though it is now rising again), but the real is now widely thought to be overvalued, pushing the current account back into deficit.

One solution is to tighten fiscal policy, which would reduce excess demand. Rapid growth in public spending is partly to blame for the excessive growth in Brazil's domestic demand. But fiscal tightening would be hard to justify in China, which already has a budget surplus. A larger surplus would boost domestic saving and hence the country's already large current-account surplus.

Either way, emerging economies need to accept that because their productivity growth is faster than the rich world's, their real exchange rates will have to rise over time. That must mean either a rise in the nominal exchange rate or higher inflation; they cannot escape both.

One can infer from the text that:

Item 3: a strong influx of capital is always desirable;