Texas Instruments BA II PLUS User Manual page 129

Breakeven
PFT = P Q N (FC + VC Q)
where:
Days between Dates
With the Date worksheet, you can enter or compute a date
within the range January 1, 1950, through December 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 I = (Y1 - YB) Q 365
Number of Days II = (Y2 - YB) Q 365
where:
Appendix: Reference Information
PFT = profit
P = price
FC = fixed cost
VC = variable cost
Q = quantity
= number of days II - number of days I
+ (number of days MB to M1)
+ DT1
(
Y
+
+ (number of days MB to M2)
+ DT2
(
+
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)
−
1 )
YB
4
−
Y 2 YB )
4
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