How can we represent negative VAT amounts?

[epsitec]

An invoice contains some positions with a VAT rate of 7.7% and some with a VAT rate of 2.5%.

In our example, the positions with the reduced VAT rate have a negative amount (refund).

Invoice:	Code	Quantity	Unit price	VAT rate	Total mount
A-100	10	100.00	7.7%	1077.00
B-200	-5	100.00	2.5%	-512.50

• Invoice total: 564.50
• VAT 7.7% total: 77.00
• VAT 2.5% total: -12.50

How can we represent this using the SWICO-String?

[epsitec]

Positive or negative VAT amounts are both represented as decimal numbers.

The correct and most compact encoding would be:

/32/7.7:1000;2.5:-500

Which means:

• 1000.00 at VAT rate 7.7% → 77.00
• -500.00 at VAT rate 2.5% → -12.50

[epsitec]

Such an example should be included in the spec.