Transient is the most hyped, abused and trendy word in GS. A transient is a short-duration signal that represents a nonharmonic attack phase of a sound source. It contains a high degree of nonperiodic components and a higher magnitude of high frequencies than the harmonic content of that sound.
But like any estimate, it's based on some rounded numbers and rules of thumb. For example, this mortgage affordability calculator assumes that your monthly mortgage payment should be no more than 28% of your monthly income, to leave enough money for other expenses and investments you'll want to make.
And the longer age limits massively improve the affordability of loans for older borrowers too. A Â£100,000 mortgage at age 65, which has to be repaid by the age of 75, costs Â£966 a month if looking at a 3% interest rate. But if the borrower can extend it to the age of 85, as would be the case with Nationwide, the cost comes down to just Â£555 a month.