For many of the financial functions, the day count basis is used:
| Basis Number | Day Count Basis | 
| 0 (or omitted) | United States of America (NASD) 30/360 | 
| 1 | Actual/Actual | 
| 2 | Actual/360 | 
| 3 | Actual/365 | 
| 4 | European 30/360 | 
[NASD is the National Association of Securities Dealers.]