Automatic Discounts not working as expected

Settings
- Only one coupon allowed

Coupons:

1) 10pc (Function Type: Coupon, Value: 10%, unlimited users, minimum order total: 200, discount type: overall)

2) 5pc (Function Type: Coupon, Value: 5%, unlimited users, minimum order total: 100, discount type: overall)

Automatic Discounts
1) 5pc
2) 10pc

Steps performed
1.) Add goods worth 250.- (25pc. @ 10.-) to the cart.
2.) Open cart -> Check that the total is 225.- (it is)
3.) Reduce the number of items to 15pc.
4.) Check that the total is 142.50 (it is)
5.) Increase the number of items to 25pc.
6.) The total should be 225.- but it is 237.50 (the 5% coupon is applied instead of the 10% coupon)

Tested:
- Reversed the order of the automatic discounts -> it is always 5% ap

What do I have to change to hava a consistent behaviour for the discount?

Thanks very much. That worked perfectly.