The demand for money is affected by several factors, including the level of income, interest rates, and inflation as well as uncertainty about the future. The way in which these factors affect money demand is usually explained in terms of the three motives for demanding money: the transactions, the precautionary, and the speculative motives.
Transactions motive. The transactions motive for demanding money arises from the fact that most transactions involve an exchange of money. Because it is necessary to have money available for transactions, money will be demanded. The total number of transactions made in an economy tends to increase over time as income rises. Hence, as income or GDP rises, the transactions demand for money also rises.
Precautionary motive. People often demand money as a precaution against an uncertain future. Unexpected expenses, such as medical or car repair bills, often require immediate payment. The need to have money available in such situations is referred to as the precautionary motive for demanding money.
Speculative motive. Money, like other stores of value, is an asset. The demand for an asset depends on both its rate of return and its opportunity cost. Typically, money holdings provide no rate of return and often depreciate in value due to inflation. The opportunity cost of holding money is the interest rate that can be earned by lending or investing one's money holdings. The speculative motive for demanding money arises in situations where holding money is perceived to be less risky than the alternative of lending the money or investing it in some other asset.
For example, if a stock market crash seemed imminent, the speculative motive for demanding money would come into play; those expecting the market to crash would sell their stocks and hold the proceeds as money. The presence of a speculative motive for demanding money is also affected by expectations of future interest rates and inflation. If interest rates are expected to rise, the opportunity cost of holding money will become greater, which in turn diminishes the speculative motive for demanding money. Similarly, expectations of higher inflation presage a greater depreciation in the purchasing power of money and therefore lessen the speculative motive for demanding money.