After I was interviewed by Paul Moulton at Manx Telecom TV the other day about the Manx Government’s sneaky budget, I spoke to him off-camera about how the Manx Government uses some pretty simple but sneaky moves to manipulate the public by fiddling with graphs in its public communications campaign.
Paul tried to put this question to Chief Minister Howard Quayle in a subsequent interview, but the Chief Minister entirely avoided the question and spoke about what some unsuccessful candidate said several years ago.
Last week, as part of its effort to sell its sneaky budget to the public, the Manx Government spent taxpayer money on a fancy colour promotional wrap-around for the Isle of Man Courier newspaper. True to its sneaky budget, it used some simple tricks to try to distort budgetary graphs which exaggerated certain aspects of the budget.
Have no doubt about this: the effect of these manipulations is to exaggerate the Government’s political aims. There is, of course, a legitimate case for the Government to inform the public of changes to laws. But such information campaigns should not use manipulated graphics in a sneaky way.
Here’s two such examples:

I imagine that the Manx Government might want to minimise the apparent increase in income tax receipts. They’ve done two key things which make it harder for the public to see at a glance what the changes to tax receipts have been:
a) They’ve removed the vertical axis of the graph; and
b) They’ve made the chart wrap-around in a circle.
This has the net effect of making it very hard to easily compare the changes from one year to the next – because the years are not in a straight and flat line.

In this graph showing the changes in the personal tax allowance, they have used different manipulations:
a) They have truncated the horizontal axis, so that instead of starting at £0, the axis starts at £9,000. This means that despite the 2020-21 number being only 36% higher than the 2016-17 number, the 2020-21 line is around 320% longer than the size of the the 2016-17 line.
b) Rather than have each line have the same width, they’ve used a thicker line for the later years. Consequently, the personal allowance looks bigger and fatter in those years.
c) Rather than have each bar run parallel to the horizontal axis, they have made the bars run at a slight incline. This makes each line a little longer (since it is on the diagonal) and harder to compare than if they were simply parallel to the horizontal axis.
So, what would these two graphs look like if they were not manipulated? Something like this:

This hypothetical graph I’ve made above clearly allows the public to easily see the change in income tax receipts from year to year, because each year is in a straight line. This allows for easy comparisons.

This hypothetical graph I’ve made shows the increase in the personal tax allowance. You can clearly see that the 2020-21 allowance is a bit more than a third bigger than the 2016-17 allowance: not three-and-a-bit times bigger. This allows for fair comparisons: each line is fairly proportional to the size of the number at issue.
Updated to add: There is a very legitimate role for public communications about budgetary matters, especially around changes to the tax code. But if there is a legitimate rationale, then that rationale should be to inform, not persuade. When used fairly, graphs can be a useful tool to inform the public. They can allow people to easily compare different pieces of information. Those graphs, however, must allow for easy and clear comparisons – they should not use sneaky graphic manipulation tricks which have the effect of misleading the public. Or, as a friend said: “Our government should be more honest and open with the public and stop these deceitful and underhand tricks. They at least owe the great Manx public that small piece of respect.”