A-58 Tables and Reference Information
8399APXA.DOC TI-83 international English Bob Fedorisko Revised: 02/19/01 1:25 PM Printed: 02/19/01 1:40 PM
Page 58 of 58
With the dbd( function, you can enter or compute a date
within the range Jan. 1, 1950, through Dec. 31, 2049.
Actual/actual day-count method (assumes actual
number of days per month and actual number of days per
year):
dbd( (days between dates) =
Number of Days II - Number of Days I
Number of Days I = (Y1
-
YB) × 365
+ (number of days MB to M1)
+DT1
+()
YYB
1
4
−
Number of Days II = (Y2
-
YB) × 365
+ (number of days MB to M2)
+DT2
+()
YYB
2
4
−
where: M1 = month of first date
DT1 = day of first date
Y1 = year of first date
M2 = month of second date
DT2 = day of second date
Y2 = year of second date
MB = base month (January)
DB = base day (1)
YB = base year (first year after leap year)
Days between
Dates