How to calculate a rate of change into a final completion time.

[stuckagain22]

Excel newbie looking for help. I have several tasks that I queue up in a game, and I would like to know when they will complete.

I have created a spreadsheet with the following columns:

Time 1 (Input is in time format: 8:45)
Time 1 % (The % of completion displayed of when the tracking started -- it should be 0% in most cases, but otherwise it will be the % completed with is displayed in the game)
Time 2 (Input is in time format: 9:00)
Time 2 % (The % of completion displayed when this time period is recorded)
Rate (I want to display the minutes per % of completion here)
Completion time (I want to display the time as to when the item will be completed, based on the rate of completion as calculated.)

I'm a little confused about how to do this.
Here are my current thoughts:

	A	B	C	D	E	F	G
1	Time 1	Time 1 %	Time 2	Time 2%	Rate in Mins / %	Percentage Left	Calculate time left	Completion Time
2					=((C2-A2)*24)/(D2-B2)	=100-(D2-B2)	=F2*E2

I really am uncertain how calculate and display the Completion Time. Could someone please help me out with this.

Thank you.

 

[Jeffrey Mahoney]

Normally you need 3 factors to determine an estimate of completion. The first 2 must be provided and the third could be the time now or a time ended
* Beg Time
* Percent Complete
* Time Now

If this were a tournament, I would use the total number of games and the games complete to get a percent complete. Calculate the number of minutes from Beg Time to Now Time and divide by the percent complete.
* Beg Time = 16:00
* Now Time = 16:30
* 30 Minutes has elapsed
* The project is 40% complete
* 30 / 40% = 75 Minutes
* Beg Time + 75 Minutes = 17:15