It appears to simply be the index your ARM will be based on. I’m assuming that using a LIBOR index mortgage(s) can be more easily and profitably combined and sold as securities and related financial instruments in that the return to the investor is more assured as the mortgage will index to the market rate.
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LIBOR stands for London Inter Bank Offer Rate. It’s the rate of interest at which banks offer to lend money to one another in the so-called wholesale money markets in the City of London. Money can be borrowed overnight or for a period of in excess of five years. The most often quoted rate is for three month money. ‘3 month LIBOR’ tends to be used as a yardstick for lenders involved in high value transactions. They tend to quote rates as ‘points above LIBOR’. So if 3 month LIBOR were (say) six per cent, a bank may choose to lend to another bank at (say) 6 and a quarter per cent. e.g. a quarter per cent above above 3 month LIBOR.
Lending to individuals tends to be based on base rates which are set by the Chancellor after consulting with the Bank of England. Base rates tend to be less volatile. Some home lenders offer mortgage rates linked to LIBOR. The lender offers funds in Sterling or in a foreign currency. Bear in mind that LIBOR-linked borrowing by individuals is higher risk, especially if you are borrowing in a foreign currency.
The LIBOR rates are set each day at 11am by leading banks but rates fluctuate throughtout the trading session according to sentiment about the outlook for base interest rates. LIBOR rates are listed each morning in the Financial Times and other newspapers.
Banks also offer to borrow money in the wholesale money markets. The rate is called the London Inter Bank Bid Rate (LIBID).
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Adjustable Rate Mortgages
Adjustable Rate Mortgages (commonly called ARMs) are flexible loans with interest rates and monthly payments that rise and fall with the economy. With an adjustable loan, the borrower shares in the benefits and risks of having the loan tied to market changes. Because the borrower shares in the risk of rising rates, lenders are able to offer lower initial interest rates than on fixed rate mortgages. The interest rate on your loan is then adjusted periodically according to whatever market index you chose when selecting your ARM.
Interest rate and monthly payment can change every six months, once a year, every three years, or every five years. For example, a one-year ARM has an adjustment period of one year, which means that the interest rate and monthly payment can change once a year. The frequency and dates of adjustments are established when you apply for your loan.
The interest rate on an adjustable mortgage changes according to a financial index. You may choose an ARM tied to any one of a variety of market indexes, such as CDs, T-Bills, or LIBOR rates. When your interest rate is up for adjustment, your lender will take the current rate of the index to which your loan is tied and add a margin, a certain set number of interest points laid out in your loan agreement, to determine your new rate. So, your interest rate and monthly payments could increase or decrease over the life of your loan, depending on the activities of the market.
Caps set forth in your loan agreement limit the amount by which the interest rate can increase at each adjustment. And ceilings, or lifetime caps, limit the total rate increase over the life of the loan. So, if you have a typical one-year ARM, your annual rate increases may be capped at 2%, which means that your interest rate can never increase by more than 2% over the previous year. Separately, your loan may have a lifetime rate cap of 6%. So, if you had an initial interest rate of 5%, the highest interest rate you could ever pay would be 11%. Caps protect you from drastic changes in interest rate, but do not guarantee you the stability of a fixed rate loan. With an ARM, you exchange the possibility of lower interest rates for the possible risk of rising rates.
An ARM might benefit you in several ways. ARMs usually come with initial interest rates that are 2-3 points lower than those on comparable fixed-rate mortgages. The lower initial interest rate can help you qualify more easily and afford the house you want to buy. You will most likely qualify for a larger loan with an ARM than with a fixed rate mortgage. You might also want to consider an ARM if you plan to move in a few years, so you are not concerned about the possibility of rate and payment increases. If you plan to move within 5 years, a 5-year ARM would even give you the advantages of a lower interest rate with none of the risks. And, even if you plan to live in your new home for longer, it might be safe to take the risks involved in an ARM if you expect your income to increase enough to cover potential increases in payments, or if you expect rates to fall.