The Percentage Increase/Decrease calculation formula is strange. . .


Scenario:

Say you want to raise all of your product prices by 10%. You go into the batch product editor and raise site price 10%.

Then you want to off 10% off to certain customers via a price group.


The prices do Not match the original prices.

Example:

Product A Price: $100

You raise price by 10%.

Product A Price: $110

Customer 1 is in Price group that gives 10% off.

Product A Price for Customer 1: $99

It *should* be $100, but its $99 instead. This becomes a problem when you are dealing with large prices like $2000.



This code is located in BVSoftware.BVC5.Core > Utilities > Utilities.vb

BV Commerce Formula:






Solution:

---

Correct Forumla:




Effectively this changes the formula to:

Amount * 1.x

Where x = Percent to add.


Or

Amount / 1.x

Where x = Percent to subtract.


Using this formula you can add 10% and then subtract 10% and end up with the original number.

Please make this modification to your code for future releases.

Yeah. . . that's what I told my bosses. . . but they didn't like not being able to go back down 10% and hit the exact number that we started from. . .


So perhaps the actual calculation isn't *wrong* per say, but its not what we were expecting it to be like.




The Add Percent seems to be fine, but its the subtracting that gives the different answer. . .


I don't know exactly what to call my calculation because technically its not subtracting 10%. . . but it reverses the 10% increase of the original number.

Normal Way:
2000 + 10% = 2200
2200 - 10% = 1980

My Way:
2000 * 1.1 = 2200
2200 / 1.1 = 2000


LOL.


Here's some fun calculations:


100 - 10% = 90
90 + 10% = 99


100 / 1.1 = 90.909090909090909090909090909091
90.909090909090909090909090909091 * 1.1 = 100


. . . . I *hate* math. . .