Y2K
Also known as Year 2000, the Y2K bug was a very common and potentially serious glitch where older computer hardware or software that processed data that included dates did not properly understand dates in the year 2000 and beyond. The systems only stored the last two digits of a date, and when the year 2000 rolled around, these systems would think the year was 1900.

Yield
The annual return an investor receives from shares, unit trusts or a stock holding. Also defined as the total proceeds from an investment.

Yield Curve
A diagram which shows the relationship of short-term rates to long-term rates.

Yield Spread Premium (YSP)
This is a payment made by a lender to a mortgage broker in connection with a borrower's mortgage transaction. The payment of a YSP by a lender affects the interest rate charged to the borrower.

Young Accounts
Refers to accounts that are new and so do not have enough payment and spend data to utilise a behaviour score. The typical definition of young accounts lies within the range of 1-6 months.

Yoyo Mode
This describes a poorly maintained Web site which is rapidly alternating back and forth between being up and being down.

YSP
Abbreviation for Yield Spread Premium. This is a payment made by a lender to a mortgage broker in connection with a borrower's mortgage transaction. The payment of a YSP by a lender affects the interest rate charged to the borrower.