Alcoa surprised Wall Street by an extra penny a share and raised its forecast for growth in aluminum demand in 2010, but the stock has settled back where it was before the earnings announcement.

In August the bank's monetary-policy committee (MPC) forecast that consumer-price inflation would fall back to its official 2% target, but only after a period of economic weakness had drawn its sting.

This paper introduces Neural net to the fields of air-materials demands analysis, and applies Back Propagation network to forecast.