Back in the day when we completed tax returns by hand, an inspector of taxes noted an unusual entry for 'other income' on a tax return she was examining.
In the space to explain a zero figure the taxpayer had written "F. All."
The Inspector wrote to the taxpayer suggesting that this was not appropriate language to use on what was a legal document.
The taxpayer responded by explaining that the Inspector had misunderstood. "I could not fit the words "Family Allowance' in the limited space available."
The Inspector wrote back pointing out that there was no requirement to enter details of Family Allowance on tax returns. The taxpayer then responded, that as regards his other income, this really was F*** All!"