“The adverse trading circumstances affecting the appellant were not in dispute. We accept that the appellant’s late payments were almost entirely due to cash flow pressures on its business. However as clearly stated in paragraph 6(2)(a) of Schedule 56, an insufficiency of funds does not qualify as a reasonable excuse. An inability to pay does not represent special circumstances, which might justify a reduction in the penalty. An exceptional or unforeseen event, which caused the insufficiency of funds, may amount to a reasonable excuse but on the facts of this appeal there was no such event. Something specific and related to the particular taxpayer is required. Adverse economic conditions and particularly late payments by customers, which happen on a regular basis, do not suffice.”