The GST form 1 allows Credit and Debit adjustments to be made in it. A worked-out example for mixed-use assets is given in the sheet . Credit Adjustments, meaning a further GST claim is made in Box 13. If actual asset use was less than the input tax claimed, a debit in Box 9 is to be made. 1. https://www.ird.govt.nz/-/media/project/ir/home/documents/forms-and-guides/gst100---gst199/gst101a/gst101a-2017.pdf
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