(redirected from Halflife)
Also found in: Dictionary, Thesaurus, Medical, Acronyms, Encyclopedia.
Related to Halflife: steam


Half Life

In a pool of mortgages underlying a mortgage-backed security, the length of time it takes for half the aggregate principal to be repaid. A half life is normally about 12 years, but this may vary depending on how often homeowners refinance their mortgages (which pays off all principal at once). Half lives are calculated for mortgage-backed securities issued or guaranteed by Freddie Mac, Fannie Mae, and Ginnie Mae.

Weighted Average Life

The amount of time for the principal on a loan or a mortgage to be paid off. The length of the weighted average life depends on the amount of principal paydowns and how often they are made. Once the WAL is calculated, one can determine how long it will take to pay off half of the remaining principal.


The length of time before half the principal on a debt is expected to be repaid through amortization or sinking fund payments. For example, a 25-year bond issue may require the issuer to retire 5% of the beginning principal commencing 5 years after the issue date. Thus, the bond issue has a half-life of 5 years plus the number of years required to retire half the issue, or 15 years. Mortgage-backed securities often have a relatively short half-life because many homeowners pay off or refinance their mortgages early. Also called average life.
Mentioned in ?
References in periodicals archive ?
If you want to live this sort of halflife, then fine.
Just as each radioactive element has its own halflife, so every advertising treatment/product
Claro que aqui no voy a hablar del original sino del Blueshift que, dicho sea de paso no requiere que tengamos el HalfLife original instalado.
013 a year, implying that a halflife on a logarithmic scale of output per worker is approximately 50 years.
Its very long halflife in the human organism causes its accumulation over the lifetime in liver and kidneys.
The mean halflife for the leaf litter in this study is [approximately]219 d, which is similar to the values reported for R.
com aimed at halflife fans and providing them with their own search engine.
2) On ``illadelph halflife,'' the Roots expand rap's reach by eschewing heavy reliance on samples in favor of backing music that dips into opera, jazz and r&b.
5)/halflife, where halflife is the number of years before one-half of the damage decays by itself.
Phosphorus-30, however, does not occur in nature, and it is radioactive, breaking down with a halflife of just under 3 minutes (which is why it doesn't occur in nature).