Why Do Mortgage Rates Change?
To understand why mortgage rates change we must first ask the
more general question, "Why do interest rates change?"
It is important to realize that there is not one interest rate,
but many interest rates!
- Prime rate: The rate offered to a
bank's best customers.
- Treasury bill rates: Treasury bills
are short-term debt instruments used by the U.S. Government
to finance their debt. Commonly called T-bills they come in
denominations of 3 months, 6 months and 1 year. Each treasury
bill has a corresponding interest rate (i.e. 3-month T-bill
rate, 1-year T-bill rate).
- Treasury Notes: Intermediate-term debt
instruments used by the U.S. Government to finance their debt.
They come in denominations of 2 years, 5 years and 10 years.
- Treasury Bonds: Long-debt instruments
used by the U.S. Government to finance its debt. Treasury bonds
come in 30-year denominations.
- Federal Funds Rate: Rates banks charge
each other for overnight loans.
- Federal Discount Rate: Rate New York
Fed charges to member banks.
- Libor: : London Interbank Offered Rates.
Average London Eurodollar rates.
- 6 month CD rate: The average rate that
you get when you invest in a 6-month CD.
- 11th District Cost of Funds: Rate
determined by averaging a composite of other rates.
- Fannie Mae-Backed Security rates: Fannie
Mae pools large quantities of mortgages, creates securities
with them, and sells them as Fannie Mae-backed securities. The
rates on these securities influence mortgage rates very strongly.
- Ginnie Mae-Backed Security rates: Ginnie
Mae pools large quantities of mortgages, secures them and sells
them as Ginnie Mae-backed securities. The rates on these securities
influence mortgage rates on FHA and VA loans.
Interest-rate movements are based on the simple concept of supply
and demand. If the demand for credit (loans) increases, so do
interest rates. This is because there are more buyers, so sellers
can command a better price, i.e. higher rates. If the demand for
credit reduces, then so do interest rates. This is because there
are more sellers than buyers, so buyers can command a lower better
price, i.e. lower rates. When the economy is expanding there is
a higher demand for credit, so rates move higher, whereas when
the economy is slowing the demand for credit decreases and so
do interest rates.
This leads to a fundamental concept:
- Bad news (i.e. a slowing economy) is good news for
interest rates (i.e. lower rates).
- Good news (i.e. a growing economy) is bad news for
interest rates (i.e. higher rates).
A major factor driving interest rates is inflation. Higher inflation
is associated with a growing economy. When the economy grows too
strongly, the Federal Reserve increases interest rates to slow
the economy down and reduce inflation. Inflation results from
prices of goods and services increasing. When the economy is strong,
there is more demand for goods and services, so the producers
of those goods and services can increase prices. A strong economy
therefore results in higher real-estate prices, higher rents on
apartments and higher mortgage rates.
Mortgage rates tend to move in the same direction as interest
rates. However, actual mortgage rates are also based on supply
and demand for mortgages. The supply/demand equation for mortgage
rates may be different from the supply/demand equation for interest
rates. This might sometimes result in mortgage rates moving differently
from other rates. For example, one lender may be forced to close
additional mortgages to meet a commitment they have made. This
results in them offering lower rates even though interest rates
may have moved up!
There is an inverse relationship between bond prices and bond
rates. This can be confusing. When bond prices move up, interest
rates move down and vice versa. This is because bonds tend to
have a fixed price at maturitytypically $1000. If
the price of the bond is currently at $900 and there are 10 years
left on the bond and if interest rates start moving higher, the
price of the bond starts dropping. The higher interest rates will
cause increased accumulation of interest over the next 5 years,
such that a lower price (e.g. $880) will result in the same maturity
price, i.e. $1000.
Effect of economic data on rates
Number of arrows indicates potential effect on
interest rates. 1 arrow=least effect, 5 arrows=max. effect
| Economic
Event |
Effect
on
Interest Rates |
Significance
of event |
| Consumer
Price Index (CPI) Rises |
     |
Indicates
rising inflation. |
| Dollar
Rises |
 |
Imports
cost less; indicates falling inflation. |
| Durable
Goods Orders Increase |
   |
Indicates
expanding economy |
| Gross
National Product Increases |
     |
Indicates
strong economy |
| Home
Sales Increase |
   |
Indicates
strong economy |
| Housing
Starts Rise |
   |
Indicates
strong economy |
| Industrial
Production Rises |
   |
Indicates
strong economy |
| Business
Inventories Rise |
   |
Indicates
weak economy |
| Leading
Indicators (LEI) Increase |
   |
Indicates
strong economy |
| Personal
Income Rises |
 |
Indicates
rising inflation |
| Personal
Spending Rises |
 |
Indicates
rising inflation |
| Producer
Price Index Rises |
     |
Indicates
rising inflation |
| Retail
Sales Increase |
  |
Indicates
strong economy |
| Treasury
Auction Has High Demand |
 |
High
demand leads to lower rates |
| Unemployment
Rises |
     |
Indicates
weak economy |
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