Discount cart rules, strange behavior

[ldetant]

I want to give a different % discount based on the total amount (tax excluded and transport cost excluded) of the order. So I created these 8 cart rules (in 'Price rules > Cart rules'):

 

 

A:18,00 % discount starting at 600,00 € (VAT excluded)

B:17,50 % discount starting at 500,00 € (VAT excluded)

C:15,00 % discount starting at 400,00 € (VAT excluded)

D:12,50 % discount starting at 350,00 € (VAT excluded)

E:10,00 % discount starting at 300,00 € (VAT excluded)

F:07,50 % discount starting at 250,00 € (VAT excluded)

G:05,00 % discount starting at 200,00 € (VAT excluded)

H:02,50 % discount starting at 150,00 € (VAT excluded)

 

I configured each one so that they can be combined with another. So it does exactly what I want! Great!

 

Only one small but annoying problem: when my client goes to the Check Out page he sees the summary of his order and he can clic on + or - to change the quantity of a product in his cart. When he does +, all works great and the cart jumpes nicely into the next (higher) discount percentage when the next level of total amount is reached. But when my client clics -, there is always one quantity where the cart gives no discount at all, and this happens when the cart should jump from one discount percentage to the following (lower) percentage.

 

Does anybody know why this is happening? Is it a bug? Or what am I doing wrong? (Please note that apart from this minor "-" problem in the summary of the cart, it all seems to do exactly what I want.)

 

(Oh yeah, I put the characters A, B, C, ... as a first character in the description of each rule because I read somewhere that these cart rules are executed in alphabetical order, and this is the order that these have to be executed)