85 = 15, 50 = 100 - Exponentiation

[zapppsr]

Hi folks:

I want to create a formula to calculate numbers from 85 to 50, starting from 85 giving me de result 15 and when it reaches 50 it gives me the result 100.

It is for a table to apply a reduction factor:

Eg.: If it reaches 85% of the goal, then reduces 15% of its prize. If it reaches 50% of the goal, then reduces 100% of its prize.

The problem is that my boss dont want a linear curve, (which I already have).

He wants a exponential curve, meaning the closest to 50 higher the reduction.

It is more a mathematical problem then a Excel one, I guess.

Tks for any help.

 

[wigi]

It is more a mathematical problem then a Excel one, I guess.

You're right.

What curve would your boss want?

 

[Rick Rothstein]

The problem is that my boss dont want a linear curve, (which I already have).

He wants a exponential curve, meaning the closest to 50 higher the reduction.

You will have to ask your boss to create one more controlling condition... without it, there are literally infinitely many exponential curves that can be drawn between the two point your current conditions establish.

 

[zapppsr]

Any curve will do... for now.

It cant only be something like

20 - 25 - 30 - 35 - 40 - 45 - 50 - 55 - .... 85 - 90 - 95 - 100

Its more like it:

17 - 18 - 20 - 21 - 23 - 26 - ..... 73 - 85 - 100

Any simple function that gives me 100 (exact) in the end will do...

 

[wigi]

Then, in the beginning (around X=85) increment with say, 1. Then, after some values, increment with 2. Then 3. And lineup so that it is 100 in the end and also discrete numbers. Additionally, you might want to have more increases of 1 than increases of 2 and more increases of 2 than increases of 3. But that's how your boss wants to have it in the end.

 

[jfish1288]

If he wants an exponential equation, it should have the form

prize reduction = C*exp^(X*percentage of goal)

Using the starting and ending points that equation can be solved to get C and X

C=100/(exp^(50*(ln(.15)/35)))
X=ln(.15)/35

so your equation would be

prize reduction = (100/(exp^(50*(ln(.15)/35))))*exp^((ln(.15)/35)*percentage of goal)

not exactly simple and it does not give whole number except at 85 and 50% of goal but you can round

 

[shg]

You could do it like this:

<TABLE style="WIDTH: 328pt; BORDER-COLLAPSE: collapse" border=0 cellSpacing=0 cellPadding=0 width=436 x:str><COLGROUP><COL style="WIDTH: 37pt; mso-width-source: userset; mso-width-alt: 2230" span=4 width=49><COL style="WIDTH: 180pt; mso-width-source: userset; mso-width-alt: 10971" width=240><TBODY><TR style="HEIGHT: 12pt" height=16><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext 0.5pt solid; BACKGROUND-COLOR: #e7e7e7; WIDTH: 37pt; HEIGHT: 12pt; BORDER-TOP: windowtext 0.5pt solid; BORDER-RIGHT: #ece9d8" class=xl37 height=16 width=49>xBeg</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: white; WIDTH: 37pt; BORDER-TOP: windowtext 0.5pt solid; BORDER-RIGHT: windowtext 0.5pt solid" class=xl36 width=49 align=right x:num>50</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: #e7e7e7; WIDTH: 37pt; BORDER-TOP: windowtext 0.5pt solid; BORDER-RIGHT: #ece9d8" class=xl37 width=49>yBeg</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: white; WIDTH: 37pt; BORDER-TOP: windowtext 0.5pt solid; BORDER-RIGHT: windowtext 0.5pt solid" class=xl36 width=49 align=right x:num>100</TD><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: #909090; WIDTH: 180pt; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8" width=240> </TD></TR><TR style="HEIGHT: 12pt" height=16><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext 0.5pt solid; BACKGROUND-COLOR: #e7e7e7; WIDTH: 37pt; HEIGHT: 12pt; BORDER-TOP: windowtext; BORDER-RIGHT: #ece9d8" class=xl37 height=16 width=49>xEnd</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: white; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl36 align=right x:num>85</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: #e7e7e7; WIDTH: 37pt; BORDER-TOP: windowtext; BORDER-RIGHT: #ece9d8" class=xl37 width=49>yEnd</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: white; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl36 align=right x:num>15</TD><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: #909090; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8"> </TD></TR><TR style="HEIGHT: 12pt" height=16><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: #909090; HEIGHT: 12pt; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8" height=16> </TD><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: #909090; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8" class=xl34> </TD><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: #909090; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8" class=xl34> </TD><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: #909090; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8" class=xl34> </TD><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: #909090; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8"> </TD></TR><TR style="HEIGHT: 12pt" height=16><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext 0.5pt solid; BACKGROUND-COLOR: #e7e7e7; WIDTH: 37pt; HEIGHT: 12pt; BORDER-TOP: windowtext 0.5pt solid; BORDER-RIGHT: #ece9d8" class=xl35 height=16 width=49>k</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: white; BORDER-TOP: windowtext 0.5pt solid; BORDER-RIGHT: windowtext 0.5pt solid" class=xl36 align=right x:num>4</TD><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: #909090; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8"> </TD><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: #909090; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8"> </TD><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: #909090; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8" class=xl34>B4: Input</TD></TR><TR style="HEIGHT: 12pt" height=16><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext 0.5pt solid; BACKGROUND-COLOR: #e7e7e7; WIDTH: 37pt; HEIGHT: 12pt; BORDER-TOP: windowtext; BORDER-RIGHT: #ece9d8" class=xl35 height=16 width=49>b</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: #f3f3f3; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl38 align=right x:num="86.585875630920796" x:fmla="=($D$1-$D$2) / (1 - EXP(-$B$4))"> 86.5859</TD><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: #909090; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8"> </TD><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: #909090; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8"> </TD><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: #909090; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8" class=xl34>B5: =(yBeg-yEnd) / (1 - EXP(-k))</TD></TR><TR style="HEIGHT: 12pt" height=16><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext 0.5pt solid; BACKGROUND-COLOR: #e7e7e7; WIDTH: 37pt; HEIGHT: 12pt; BORDER-TOP: windowtext; BORDER-RIGHT: #ece9d8" class=xl35 height=16 width=49>a</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: #f3f3f3; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl38 align=right x:num="13.414124369079204" x:fmla="=$D$1 - $B$5"> 13.4141</TD><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: #909090; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8"> </TD><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: #909090; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8"> </TD><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: #909090; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8" class=xl34>B6: =yBeg - b</TD></TR><TR style="HEIGHT: 12pt" height=16><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: #909090; HEIGHT: 12pt; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8" height=16> </TD><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: #909090; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8" class=xl34> </TD><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: #909090; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8"> </TD><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: #909090; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8" class=xl34> </TD><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: #909090; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8" class=xl34> </TD></TR><TR style="HEIGHT: 12pt" height=16><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext 0.5pt solid; BACKGROUND-COLOR: #e7e7e7; WIDTH: 37pt; HEIGHT: 12pt; BORDER-TOP: windowtext 0.5pt solid; BORDER-RIGHT: windowtext 0.5pt solid" class=xl33 height=16 width=49>x</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: #e7e7e7; WIDTH: 37pt; BORDER-TOP: windowtext 0.5pt solid; BORDER-RIGHT: windowtext 0.5pt solid" class=xl33 width=49>y</TD><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: #909090; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8"> </TD><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: #909090; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8"> </TD><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: #909090; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8" class=xl34> </TD></TR><TR style="HEIGHT: 12pt" height=16><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: white; HEIGHT: 12pt; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8" class=xl40 height=16 align=right x:num="50">50 </TD><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: #f3f3f3; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8" class=xl39 align=right x:num="100" x:fmla="=$B$6 + $B$5 * EXP(-$B$4 * ($A9-$B$1) / ($B$2-$B$1))">100.00 </TD><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: #909090; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8"> </TD><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: #909090; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8"> </TD><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: #909090; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8" class=xl34>B9: =a + b * EXP(-k * (x-xBeg) / (xEnd-xBeg))</TD></TR><TR style="HEIGHT: 12pt" height=16><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: white; HEIGHT: 12pt; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8" class=xl40 height=16 align=right x:num="55" x:fmla="=A9+5">55 </TD><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: #f3f3f3; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8" class=xl39 align=right x:num="62.310737447770208" x:fmla="=$B$6 + $B$5 * EXP(-$B$4 * ($A10-$B$1) / ($B$2-$B$1))">62.31 </TD><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: #909090; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8"> </TD><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: #909090; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8"> </TD><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: #909090; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8"> </TD></TR><TR style="HEIGHT: 12pt" height=16><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: white; HEIGHT: 12pt; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8" class=xl40 height=16 align=right x:num="60" x:fmla="=A10+5">60 </TD><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: #f3f3f3; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8" class=xl39 align=right x:num="41.02692787941762" x:fmla="=$B$6 + $B$5 * EXP(-$B$4 * ($A11-$B$1) / ($B$2-$B$1))">41.03 </TD><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: #909090; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8"> </TD><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: #909090; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8"> </TD><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: #909090; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8"> </TD></TR><TR style="HEIGHT: 12pt" height=16><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: white; HEIGHT: 12pt; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8" class=xl40 height=16 align=right x:num="65" x:fmla="=A11+5">65 </TD><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: #f3f3f3; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8" class=xl39 align=right x:num="29.007574910806778" x:fmla="=$B$6 + $B$5 * EXP(-$B$4 * ($A12-$B$1) / ($B$2-$B$1))">29.01 </TD><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: #909090; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8"> </TD><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: #909090; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8"> </TD><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: #909090; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8"> </TD></TR><TR style="HEIGHT: 12pt" height=16><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: white; HEIGHT: 12pt; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8" class=xl40 height=16 align=right x:num="70" x:fmla="=A12+5">70 </TD><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: #f3f3f3; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8" class=xl39 align=right x:num="22.220028474624474" x:fmla="=$B$6 + $B$5 * EXP(-$B$4 * ($A13-$B$1) / ($B$2-$B$1))">22.22 </TD><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: #909090; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8"> </TD><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: #909090; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8"> </TD><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: #909090; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8"> </TD></TR><TR style="HEIGHT: 12pt" height=16><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: white; HEIGHT: 12pt; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8" class=xl40 height=16 align=right x:num="75" x:fmla="=A13+5">75 </TD><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: #f3f3f3; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8" class=xl39 align=right x:num="18.386977998143145" x:fmla="=$B$6 + $B$5 * EXP(-$B$4 * ($A14-$B$1) / ($B$2-$B$1))">18.39 </TD><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: #909090; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8"> </TD><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: #909090; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8"> </TD><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: #909090; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8"> </TD></TR><TR style="HEIGHT: 12pt" height=16><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: white; HEIGHT: 12pt; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8" class=xl40 height=16 align=right x:num="80" x:fmla="=A14+5">80 </TD><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: #f3f3f3; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8" class=xl39 align=right x:num="16.222384931503662" x:fmla="=$B$6 + $B$5 * EXP(-$B$4 * ($A15-$B$1) / ($B$2-$B$1))">16.22 </TD><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: #909090; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8"> </TD><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: #909090; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8"> </TD><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: #909090; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8"> </TD></TR><TR style="HEIGHT: 12pt" height=16><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: white; HEIGHT: 12pt; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8" class=xl40 height=16 align=right x:num="85" x:fmla="=A15+5">85 </TD><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: #f3f3f3; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8" class=xl39 align=right x:num="15" x:fmla="=$B$6 + $B$5 * EXP(-$B$4 * ($A16-$B$1) / ($B$2-$B$1))">15.00 </TD><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: #909090; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8"> </TD><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: #909090; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8"> </TD><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: #909090; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8"> </TD></TR></TBODY></TABLE>

The cells at the upper left are the two endpoints of the curve. k is the parameter that controls the shape, and can be any positive or negative number (i.e., <> 0).

 

[zapppsr]

Thanks for all contribution... I will give them a try

 

[zapppsr]

shg, that was a very nice solution. It works very nice, specially the k that controles de intensity of the curve.

I'm already putting it to use.

Thank you very much for sharing.

And thanks everyone, that gave me some leads on that.

 

[shg]

You're welcome, I'm pleased you found it useful.