Why is it.....

[KARL]

...that people insist on saying the interest rate at 0.5% is half of one percent. Is this to prevent confusion that it might be of one-hundred-and-twenty-one-seven-hundred-and-fifty-sixths (121/756)?

[KARL]

oops, should read ....'that it might be half of one-hundred-....'

Sorry

[factor-fiction]

I think one per cent means one part per hundred, so 2% = two parts per hundred , etc.

Economists and mathematicians prefer to say 'half of one per cent' rather than 'a half percent' since the latter in effect means a 'half part per hundred' which could be confused I suppose with 50%.

But I don't know why we don't just say 0.5%, since that shouldn't lead to any confusion. After all, the bank of England could in theory choose to change rates by for example 0.3% and it would be a bit unwieldy to say 'three tenths of one percent'.

Anyway, a worringly large proportion of the poulation don't understand percentages and don't know what 0.5% means.

[R1Geezer]

They should say "Half of one percentage point", half of one percent would have brought them down to 0.95!

[factor-fiction]

Yes, RIGeezer, the common practice is to refer to percentage points in these cases.
In your last sentence I take it you meant 0.995% rather than 0.95.

[KARL]

Now I understand - nobody understands. Half of one percent is 0.5% which is the same as half a percent (a percent being one percent being 1%). You see, one is one whether it is a kilo a stone or percent (yes, one hundreth of the whole). Half of one is a half is 0.5. If you reduce something by half a percent then it is 0.5% less than it was before - yes, if 1% has been reduced by 0.5% then strictly speaking it is 0.995% but the rate was reduced to half of what it was so reduced by 50%. It was reduced to half a percent, 0.5% (yes, which is half of one). However, when people tell me they have lost half a stone then I get seriously worried because half a stone is actually just a stone that is half the size of what it used to be. For what reason did they halve it and how did they come to lose one half - where is the other half for comparison purposes and where do you start looking for the lost half ......but that is another story.

[KARL]

Just had a thought - why don't the same people say 3.5% is "three and a half of one percent" ?