FORECAST Function Guidance

[mrhartley]

Hi,

Just stumbled across the FORECAST function a couple of days ago and was hoping that someone can explain the basics for me (maybe via a guide) or point out how might I use FORECAST in the following simple example.

I have tried it myself and I think I have been successful but I am looking for clarification.

example 1 - in column I3 I would like to forecast the next % base don the previous %

DTMA Trend.xls
	B	C	D	E	F	G	H	I
2	Key Performance Indicators	Sep-05	Oct-05	Nov-05	Dec-05	Jan-06	Feb-06	Mar-06
3	Test KPI	90.00%	90.54%	96.05%	94.19%	92.45%	95.06%
Sheet1

example 2

forecast.xls
	B	C	D	E	F	G	H	I
1		1	2	3	4	5	6	7
2	Key Performance Indicators	Sep-05	Oct-05	Nov-05	Dec-05	Jan-06	Feb-06	Mar-06
3	Test KPI	90.00%	90.54%	96.05%	94.19%	92.45%	95.06%	95.97%
Sheet1

Have I got it right?

Thanks In Advance for any pointers. Like I say, just found this function and would like to try an take advantage of it more.
Regards
~Mark

 

[timorrill]

Mark,

Here are a couple of websites that are worth checking out:

http://www.techonthenet.com/excel/formulas/forecast.php

http://exceltips.vitalnews.com/Pages/T0590_Using_the_FORECAST_Function.html

Hope this helps!

 

[mrhartley]

Thank you for those links.

Will read up

~Mark

 

[mrhartley]

They were good thanks.

That taught me that not only will FORECAST predict the next iteration based on a pair of numbers but will also predict when a target might be reached.

EDIT -With Simple Example

forecast.xls
	C	D	E	F
8	Date	Weight		24/10/2006
9	05/08/2006	89		predicted date for ideal weight of 70 kilos
10	12/08/2006	87
11	19/08/2006	85
12	26/08/2006	84
13	02/09/2006	82
14	09/09/2006	81
15	16/09/2006	79
16	23/09/2006	77
17	30/09/2006	76
18	07/10/2006	74
19	what I will weigh on the 7th october
Sheet1

Thanks again
~Mark