On Sunday morning, a little over eight hours after the rate for value-added tax (VAT) went from 14% to 15%, popular trade unionist Zwelinzima Vavi tweeted that the "the price of everything is going up due to a 7% increase of VAT!"
He was quickly accused of lying...
Vat was 14% nd now it has been increased by 1% to 15% ......stop lying— Boti Jabu (@RSAinvestigator) April 1, 2018
... and of trying to score political points...
Zizo baba... End of story... 7% is political point scoring by Vavi to stay relevant... What is the membership percentage of the federation kanene Mr. Vavi?— Sivuyisiwe Thomas Walaza-Sitsholwana (@jesus_isblack) April 1, 2018
... and even a "maths graduate" said he had got it wrong.
????as a maths graduate I am failing to understand why 1% increase ==> 7% increase. I will look that up and inform myself— Donsie?? (@Donsie_Prince) April 1, 2018
Luckily the professional fact-checkers and calculators got involved...
Let's get this #VAThike right: it has increased by 1 percentage POINT from 14% to 15%, which is an increase of 7.1% in the VAT RATE. The impact is an increase of 0.877% on what you PAY (from R114 to R115 on something that costs R100 excl. VAT) #mathsmatter #Budget2018— Nerina Visser, CFA (@Nerina_Visser) February 21, 2018
... as did many others, trying in different ways to explain how a single percentage point increase equates to a higher increase in prices measured as a percentage.
Claim a refund of your school fees. 1% increase in VAT is a 7.1% increase in the price of an item.— Miss_Barbara-B (@Eng_Precious) April 1, 2018
If anything Vavi was slightly too aggressive in rounding down the actual increase – which is really 7.1428571429%.