| Year-on-year | Compared to the corresponding data from one year previously. For example, if a firm's 2nd-quarter profit rose 12% y/y, then its 2nd-quarter profit this year was 12% higher than its 2nd quarter profit the year before. Same as year-over-year. |
| Yield | The amount of return on an investment, normally expressed as percent per year; the interest rate. |
| Yield curve | The variation of asset yields as the maturity of the asset rises. Also called the term structure of interest rates. Normally, the yield on otherwise comparable assets rises with their time to maturity. |
| Yield spread | The difference between the yield on a particular bond and the yield on an otherwise comparable bond that is considered, like a U.S. treasury bill, to have essentially zero risk. The spread is an indicator of the risk of the bond and thus, as in the case of bonds issued by emerging market governments, the economic strength of those governments. |
| YOY | Year-on-year |
| Yuan | The principal unit of the renminbi, the currency of China. Each yuan is subdivided into ten jiao, which are in turn subdivided into ten fen. |
| Y/Y | Year-on-year |