The number of days in the month and year convention to be followed for the given asset.
Possible enumeration values:
ACT_ACT
1
ACT_365
2
ACT_365Japanese
3
ACT_365ISDA
4
ACT_360
5
_30_360
6
_30_360ISDA
7
_30_360PSA
8
_30_360SIA
9
_30E_360
10
_30E__360
11
_30_360ISMA
12
Pro_Rate
13
ACT_365Fixed
14
_30_365
15
_30_366
16