**Calculating Where Events Fall**

I You start knowing that 2 ratios are equal.

# of years ago event took
place
# of days from the end of a 365 day year

------------------------------------------
= ------------------------------------------------------

Scale
365

II You can then solve the equation for the unknown "# of days from
the end of a 365 day year".

# of years ago event took place
X
365

-----------------------------------------------------
=
# of days from the end of a 365 day year

Scale

III Subtract the result in step II from 365 to get the "day" of
the year on which the event fell.

365 -
# of days from the end of a 365 day year
=
day of year on which event fell

IV Look up the result from step III in the following table to get the
Month. (Find the highest number in the left column that is less than or equal to the
"day" from step III. The Month you want is to the right of the number you found
in the table.)

example: 30.9854 would
give you January

0
January

31 February

59 March

90 April

120 May

151 June

181 July

212 August

243 September

273 October

304 November

334 December

365 December

V Subtract the number to the left of the Month you found in step IV from
the "day" you come up with in step III to get the "day of the month".
If your result contains a fraction, add 1 to the integer portion of the result to get the
"day of the month".

example:
30.9854 -
0 =
30.9854
30 +
1 =
31

VI If the result in step III has no remainder, then the event occurred
at 12 am exactly. If there is a remainder, then you can proceed to calculate the
"time of day" at which the event occurred using steps VII through IX.

VII Multiply the decimal portion of the result in step III by 24. The integer
portion of this result is the hour of the day. If the integer portion of this result is
more than 12, subtract 12 from it to get a PM hour; otherwise you have an AM hour.

(exception: 0 = 12 am and 12 = 12 pm)

example: .9854 *
24 =
23.6496
23 -
12 =
11 pm

VIII To get the minute of the hour, multiply the decimal portion of the result
in step VII by 60. The integer portion of this result is the minute of the hour.

example:
.6496 *
60 =
38.94
38 minutes

IX To get the # of seconds of the next minute, multiply the decimal
portion of the result in step VIII by 60. Drop the decimal portion of your result. The
result is the number of whole seconds past the previous whole minute.

example:
.94 *
60 =
56.4
56 seconds

return to the Putting Time In Perspective page

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original web posting: Wednesday, September 9, 1998

last modified:
Tuesday, March 16, 2004