Pegging in commodities trading : Control by commodity exchanges of price fluctuations by tying the daily trading limits to the previous trading day’s settlement( close ) price. In currency trading : Control of exchange rate fluctuations by a government through (1) tying a currency’s value to the value of a stronger currency, (2) buying and selling own currency to increase or decrease its demand, (3) securities trading : manipulation of a new issue’s market price by its underwriter through large purchases on the stockmarket. Siimilar manipulation of already issued securities is illegal.